Config to override engine functionality

* Adds configuration in engine to override functionality
Config to override engine functionality

* Adds carrierwave and gem dependencies to Gemfile
* Adds carrierwave and gem dependencies to gemspec
Config to override engine functionality

* Adds aws keys to carrierwave
* Adds uploader to badge model
* Creates image uploader
Config to override engine functionality

* Updates badges views to show the image of the badge
Config to override engine functionality

* Adds figaro gem to the party
* Adds file with important keys to the gitignore
Config to override engine functionality

* Adds file to gitignore
* Fix carrierware to use environment variables
Config to override engine functionality

* Adds specs for uploader
ugly way to fix this
Adds uploaders support in specs
adds special configuration to test environment
adds conditions to carrierwave for environments
Merge pull request #12 from zalapeach/feature/config-to-override-engine

Feature/config to override engine