Rspec 3, flexible initialize block, fixes method_missing approach (prescribed use by twilio-ruby)

[rosskevin]

This solves #19, #18, and #13. The rspec test is fully updated and all tests pass.

The method_missing approach appears to be the prescribed use in the README such as:

@client.messages.create(
  from: '+14159341234',
  to: '+16105557069',
  body: 'Hey there!'
)

This now works and is tested the same as the approach using @client.account.messages etc.

[afeld]

Working great for me. Thanks for the fix! 👍

[rosskevin]

@manlycode is this maintained or abandoned?

[monfresh]

@manlycode Hi. Just wondering if you were planning on merging this PR. Thanks!