Re-dded a div causing events not to show at the non-montly view

 * The div is the gradient one. Now is added, but empty, till the
   UI designer takes a look at this.
Added a border to a calendar event

 * Thus two consecutive events can be differentiated better
Merge pull request #9 from Zentyal/mjulian/event-gradient-fix

Re-added a div causing events not to show at the non-montly view