Fix Content not showing w/ Angular 1.2+ | Long time getting Content

Hi everyone,

This Pull Request is about the bug a lot of people had (and so I did) with the new versions of AngularJS (from 1.2). The users of the directive couldn't get their contents when the response containing the information took too long to arrive.
The addition is one $watch allowing to prepare the instance of tinymce.

Hope this fix can help ! :smiley: 

Maxoumime

PS: Sorry for my English, hope it wasn't too awful. :sweat_smile: