[Feature] Add frame option for collage

[andi34]

Following use case:
I used a specific frame for single photos (text + funny picture of bridal couple), but it's simply too much on a collage.

Feature:
This RP implements the option to set the frame option on single picture and collages separately, as well the option to use different frames for single picture and collages.

Need help with:

• language translation for es / fr / gr

Edit by Andreas Blaesius:

• Update commit for Photobooth 2.3+
• add missing manual strings
• add @philippselle to contributors

Initial PR from andreknieriem#243