DAR-36: CKEditor tracking

For more details on what's being tracked: https://docs.google.com/a/wikia-inc.com/spreadsheet/ccc?key=0Ahq3QVBqbE1xdElQRmRvbk4tMUc3VXVmeWl6WlFWSEE#gid=4

Along with this commit also comes two new generic tracking actions: 'hover' and 'keypress'