storage is unusable in v0.2.0

[dnabil]

When i use DeleteBucket(), it panics because nil pointer error.
The error is caused by this line https://github.com/nedpals/supabase-go/blob/master/storage.go#L166

It tries to access s.client, but is a nil pointer.
The same with any method that tries to access Storage's client field in storage.go.

PROBLEM:
When initializing the supabase client with CreateClient, the in v.0.2.0 Storage's client is not SET.
(idk if it's the only problem).

FIX:
this commit (almost 5 months ago) already fixes the problem by setting the storage's client field in CreateClient(), but isn't present in the latest version (v0.2.0).

pls release a new version with the fix

[jackmerrill]

I've created a pull request (#25) to fix a few of these issues.