- Remove strict flags from files, which are using FFmpeg stuff
We're still using some symbols which are marked as deprecated.
Ideally, we shall switch to new API, but it's a bit larger challenge
because we don't want to break compatibility withotu actual need.
- Replace MAKE_ID with BT_MAKE_ID in bullet library.
This is needed to prevent re-definition of MAKE_ID in bullet library.
Seems it's only used to read blender files, so should be quite safe
change.