All events endpoint

This is the all BridgeTroll and external events JSON endpoint for RailsBridge.  This way we can grab all events and then process them on our side.

I added tests to the events controller spec to ensure the correct events where being returned from this and the past events endpoint.

Currently the past events are a bit odd in that they return future external events, but that functionality is definitely a needed and used feature right now for RailsBridge to display upcoming external events with BridgeTroll upcoming events.

Will give a heads up once RailsBridge switches to using all events endpoint.

Let me know if you have any questions or something needs changing, etc...  Thanks!