Add .captcha, .code and .verify calls
Relying on String#blank? requires activesupport as a runtime dependency
Documentation for .captcha, .code and .verify
Adds an options to send the app_key with each method (useful for multiple app accounts)
Updates the README regarding the option to send the app_key with every call
Merge pull request #1 from danevron/master

Support multiple application accounts
Make token optional for 'code' calls
Merge pull request #1 from rauchy/master

Add pin-code verification calls