Fixed License display.
Fixed i18n.
Fixed status header.
Renamed API class.
Updated i18n shim.

A performance issue was fixed in the shim(s) generated by generateJsonI18n.php, so it needed to be updated.
Added Test bootstrap.
Added types to Subscription.
Moved API functionality to helper class.
Added tests for accepting/declining API requests.
Fixed SubscriptionTest in case another test uses the subscription tables.
Added tests for subscribe and unsubscribe events.
Added tests for incoming push data.
Fixed phpunit tests.
Added a few SubscriberClient tests.
Added coverage output.
Added more SubscriberClient tests.
Added more API tests to reach 100% code coverage. Yay!
Refactored API tests.
Added some docs.
Merge branch 'feature/refactoring' into develop