[Shotwell] Face branch updated

[Ricardo <ricardofantin gmail com>]

Hello,
I just made a pull-request to the face branch. Every function were
updated and all functionalities are present in this version.

I never contributed to a big program, so I will try my best to made
all corrections asked.

After, I will remove the c++ code, and correct the opened bugs against
the faces branch.

Regards,
Ricardo.