Show all event logs

* Don't limit logs to the last 100 events
* Use kaminari to paginate the events

https://www.agileplannerapp.com/boards/173808/cards/8984

![screen shot 2014-12-24 at 10 56 52](https://cloud.githubusercontent.com/assets/319055/5547908/9efac4b6-8b5b-11e4-9619-14a5a1c4be44.png)