Add filter branch feature

Hi, 

I've implemented the available `filterText` function of the api allowing the administrator to restrict available branches in the list. 
The administrator just add patterns like `dev` or `dev,feature` and the resulting list will only contains branches that have `dev` in the first case in their name or in the second branches that have `dev` or `features`.
If you have any questions about my modifications just contact me.

Regards 
Guillaume Le Floch