:gem: Add figaro and recaptcha gems

- Figaro is for decoupling configuration information so API
  keys don't have to be hardcoded in application
- Recaptcha is ruby client library for reCaptcha by Google.
:gem: rails g figaro:install
Add example application.yml to document what keys are expected
Add initializer for recaptcha
:sparkles: rails g controller registrations
Configure recaptcha
Refactor out registrations form to a partial
Fix issues with styling
handle styling of flash messages in home page