CanCan updated to new version
Sorted Menu Entries and removed active admin comments
added cancan ability handling to active admin
rules hanlding now grouped into separate box
added missing translations for active admin
Separated ActiveAdmin from normal abilities.

Attention: This is not done yet and buggy. I 
need help to fix this and get it work.

Current problem: 

The ability to edit an event
that is assigned to the user is defined in #21,
but we also have to add the ability to edit
an event if it is in a region the user
is able to edit (line #26)

Currently I only can do one and not the other. If
I try to mix both abilities, it does not work. Sadly
the doc from cancan says this should work.