Adds Danger to CI (Instabug#12)

Adds Danger to automate various checks for PRs. Starting with just a rule to make sure PRs have a summary of changes.

Author: HeshamMegid

.circleci/config.yml

@@ -6,6 +6,8 @@ jobs:
       - image: cirrusci/flutter
     steps:
       - checkout
+      - run: bundle check || sudo bundle install        
+      - run: bundle exec danger
       - run: flutter doctor
       - run: pub get
       - run: dartanalyzer --options analysis_options.yaml lib

Dangerfile

@@ -0,0 +1,4 @@
+# Make sure PR has a description.
+if github.pr_body.length < 3 && git.lines_of_code > 10
+  fail "Please provide a summary of the changes in the pull request description."
+end

Gemfile

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+source "https://rubygems.org"
+
+git_source(:github) {|repo_name| "https://github.com/Instabug/Instabug-Flutter/" }
+
+gem 'danger'

Gemfile.lock

@@ -0,0 +1,53 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    addressable (2.5.2)
+      public_suffix (>= 2.0.2, < 4.0)
+    claide (1.0.2)
+    claide-plugins (0.9.2)
+      cork
+      nap
+      open4 (~> 1.3)
+    colored2 (3.1.2)
+    cork (0.3.0)
+      colored2 (~> 3.1)
+    danger (5.16.1)
+      claide (~> 1.0)
+      claide-plugins (>= 0.9.2)
+      colored2 (~> 3.1)
+      cork (~> 0.1)
+      faraday (~> 0.9)
+      faraday-http-cache (~> 1.0)
+      git (~> 1.5)
+      kramdown (~> 1.5)
+      no_proxy_fix
+      octokit (~> 4.7)
+      terminal-table (~> 1)
+    faraday (0.15.4)
+      multipart-post (>= 1.2, < 3)
+    faraday-http-cache (1.3.1)
+      faraday (~> 0.8)
+    git (1.5.0)
+    kramdown (1.17.0)
+    multipart-post (2.0.0)
+    nap (1.1.0)
+    no_proxy_fix (0.1.2)
+    octokit (4.13.0)
+      sawyer (~> 0.8.0, >= 0.5.3)
+    open4 (1.3.4)
+    public_suffix (3.0.3)
+    sawyer (0.8.1)
+      addressable (>= 2.3.5, < 2.6)
+      faraday (~> 0.8, < 1.0)
+    terminal-table (1.8.0)
+      unicode-display_width (~> 1.1, >= 1.1.1)
+    unicode-display_width (1.5.0)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  danger
+
+BUNDLED WITH
+   1.16.1