Updating gitignore
Change migration to add otp secret key.
Adding otp methods.
Misc renames for otp secret key.
Adding rotp dependency.
Adding rspec.
Introducing first spec to test otp code.
Test otp authentication.
Only max_login_attempts is now configurable.
Spec: validate that send_two_factor_authentication_code can be overwritten
otp_column_name: do not allow for override.
Controller: authenticate using new one time password algorithm.
Allowing both config and override of allowed otp drift.
Allow for successful rollback of migration.
Remove code argument from send_two_factor_authentication_code
Modifying readme based on changes to gem.
Adding clarification around google authenticator.
Adding unique index to otp secret key.

This prevents the potential of a leaking of a single secret key from effecting others.
Merge pull request #16 from checkdin/master

Use time-based authentication codes