New features:
-Image drawtype
-Constant-length line drawtype
-Keyframeable gravity strength random range
-Defined constants for drawtypes (eg. PyIgnition.DRAWTYPE_CIRCLE)
Bugfixes:
-Creating two keyframes on the same frame would previously crash the program. This has now been fixed, and the program now interprets this situation as a sudden change between the two keyframes (immediately switching to the values associated with the second).