Refactors/http service encode params

[asheren]

This PR is not meant to change any functionality, the goal was simply to refactor the encoded_params method. No new tests were added and no functionality was changed.

Tested back to ruby-2.2.3
There appeared to be test breakage at ruby-2.3 and prior to ruby-2.2, ByeBug breaks, but those breakages seem to be unrelated to this refactor.

• My PR has tests and they pass!
• The live tests pass for my changes (LIVE=true rspec -- unrelated failures are okay).
• The PR is based on the most recent master commit and has no merge conflicts.

[asheren]

For sanity sake, here are the tests that failed on master:

Finished in 3 minutes 0 seconds (files took 0.89244 seconds to load)
603 examples, 20 failures, 5 pending

Failed examples:

rspec ./spec/cases/test_users_spec.rb:128 # Koala::Facebook::TestUsers when used without network #create creates a test user when not given installed, ignoring permissions
rspec ./spec/cases/test_users_spec.rb:121 # Koala::Facebook::TestUsers when used without network #create creates a test user when not given installed
rspec ./spec/cases/api_spec.rb[1:13:3:1:1] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with GraphCollection when getting a collection gets a GraphCollection when getting connections
rspec ./spec/cases/api_spec.rb[1:13:2:4] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets multiple objects
rspec ./spec/cases/api_spec.rb[1:13:2:9] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can access connections from public Pages
rspec ./spec/cases/api_spec.rb[1:13:2:18] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can post a message whose attachment has a properties dictionary
rspec ./spec/cases/api_spec.rb[1:13:2:22] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can comment on an object
rspec ./spec/cases/api_spec.rb[1:13:2:7] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets data about 'me'
rspec ./spec/cases/api_spec.rb[1:13:2:11] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can access connections from users
rspec ./spec/cases/api_spec.rb[1:13:2:23] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can verify a comment posted about an object
rspec ./spec/cases/api_spec.rb[1:13:2:21] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can verify a message with an attachment posted to a feed
rspec ./spec/cases/api_spec.rb[1:13:2:15] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can delete likes
rspec ./spec/cases/api_spec.rb[1:13:2:5] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets multiple objects if they're a string
rspec ./spec/cases/api_spec.rb[1:13:2:26] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can get information about an access token
rspec ./spec/cases/api_spec.rb[1:13:2:24] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can like an object
rspec ./spec/cases/api_spec.rb[1:13:2:8] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets multiple objects
rspec ./spec/cases/api_spec.rb[1:13:2:2] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets public data about a Page
rspec ./spec/cases/api_spec.rb[1:13:2:6] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets private data about a user
rspec ./spec/cases/oauth_spec.rb:615 # Koala::Facebook::OAuth for cookie parsing for fetching access tokens protected methods fetches a proper token string from Facebook when asked for the app token
rspec ./spec/cases/realtime_updates_spec.rb:154 # Koala::Facebook::RealtimeUpdates #subscribe in practice sends a subscription request

and here are the ones that failed on this branch:

Finished in 3 minutes 21.5 seconds (files took 0.90898 seconds to load)
603 examples, 20 failures, 5 pending

Failed examples:

rspec ./spec/cases/api_spec.rb[1:13:2:4] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets multiple objects
rspec ./spec/cases/api_spec.rb[1:13:2:18] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can post a message whose attachment has a properties dictionary
rspec ./spec/cases/api_spec.rb[1:13:2:8] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets multiple objects
rspec ./spec/cases/api_spec.rb[1:13:2:15] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can delete likes
rspec ./spec/cases/api_spec.rb[1:13:2:9] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can access connections from public Pages
rspec ./spec/cases/api_spec.rb[1:13:2:24] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can like an object
rspec ./spec/cases/api_spec.rb[1:13:2:7] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets data about 'me'
rspec ./spec/cases/api_spec.rb[1:13:2:2] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets public data about a Page
rspec ./spec/cases/api_spec.rb[1:13:2:6] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets private data about a user
rspec ./spec/cases/api_spec.rb[1:13:2:22] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can comment on an object
rspec ./spec/cases/api_spec.rb[1:13:2:26] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can get information about an access token
rspec ./spec/cases/api_spec.rb[1:13:2:21] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can verify a message with an attachment posted to a feed
rspec ./spec/cases/api_spec.rb[1:13:2:5] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token gets multiple objects if they're a string
rspec ./spec/cases/api_spec.rb[1:13:2:11] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can access connections from users
rspec ./spec/cases/api_spec.rb[1:13:2:23] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with an access token can verify a comment posted about an object
rspec ./spec/cases/api_spec.rb[1:13:3:1:1] # Koala::Facebook::API with an access token it should behave like Koala GraphAPI with GraphCollection when getting a collection gets a GraphCollection when getting connections
rspec ./spec/cases/test_users_spec.rb:128 # Koala::Facebook::TestUsers when used without network #create creates a test user when not given installed, ignoring permissions
rspec ./spec/cases/test_users_spec.rb:121 # Koala::Facebook::TestUsers when used without network #create creates a test user when not given installed
rspec ./spec/cases/oauth_spec.rb:615 # Koala::Facebook::OAuth for cookie parsing for fetching access tokens protected methods fetches a proper token string from Facebook when asked for the app token
rspec ./spec/cases/realtime_updates_spec.rb:154 # Koala::Facebook::RealtimeUpdates #subscribe in practice sends a subscription request