OSX build: Fix error message at the end.
OSX build: Don't bundle Python 2.x.
Fix Bug #440 - CaretMenu/Keyframe/addkeyframe, inactive until a keyframe is added by keyframes panel

add the missing menuitem actions in the "ustring ui_info"
Fix #341 - Add first keyframe when new document created.
When rendering the rotated result use SOURCE operator instead of OVER.
When top left and bottom right changes at the same time, do it with a set_tl_br function instead of set_tl and then set_br because it could lead to a dimension of zero in one of the dimensions.
Do not forget to destroy Cairo context when not more used.
Fixed Enhancement #409  -  UI : Label + Shortcut on tooltip describing "action"