Merging gitfiletree update with Issues90 and 91 tests active for git

gitfiletree is green with the new issues; I hope that Travis will agree with me.

But it seems I'm missing a lot of code around some of the new solved issues (script and traits support). Since gitfiletree derive its code from Filetree, I'm sure I am missing things, but I have nothing to test against? I'll do a review of all the changes and port them one by one.