Context Menu enabled in trunk

[Abdelrazak Younes]

Dear all,

As Juergen already uncovered I am pleased to announce preliminar basic 
support for context menus in trunk. Still a lot of ui polishing to do 
before this feature is really useful. Right now we only get the 'edit' 
menu when right clicking somewhere in text.

The MenuBackend class needs to be cleaned up and complemented with a new 
kind of menus as it is very much oriented toward menubar currently.
aAll that remains is the ui polishing. Quite frankly, I think all of 
MenuBackend should be merged into qt4/Menus but I won't do that as I 
know JMarc disagree. Right now, the way this code is working is very 
complicated IMO.

Abdel.