This is mostly intended for total conversions to allow them to set
themselves apart from FS2 based mods. It uses the new in-memory
filesystem to support a default icon in case no icon was specified by
the mod.
This disables all mouse grabbing which is useful for debugging when SDL gets interrupted without giving up
control of the mouse. That usually leads to problems since you can't
interact with the debugger window anymore.
The APNG changes required some additional work. A cursor now owns the
bitmap handle that will be used for the cursor. This is required in
order to support variable FPS cursors.
asarium