Blender Git Loki

Bugfix with py operator api and modal operators. Modal operators would keep a reference to Reports locally allocated in the api functions, which would crash and burn later when the operator would actually stop.

This commit introduces a flag at the Reports level that can be used to indicate that it needs to be freed (on top of the flag already existing in the operator, which I guess could be removed).

Reports for operators called through python are only persisted if they indicate that they are running modal.