Add support for events

:bomb: WIP

This PR is to add support for listing events on the 24pullrequest website. I am opening up the PR early to get some early direction and feedback.

### To do -

- [ ] Add event model and attributes
- [ ] Add map with events
- [ ] Restrict `event#new` and `event#edit` to logged in users
- [ ] Move all content into the locale files
- [ ] Add events link to the homepage
Redundant curly braces around a hash parameter.<br>Use the new Ruby 1.9 hash syntax.<br>Surrounding space missing for operator '=>'.