Add documentation to the public API.
Add documentation to the public API.

libimobiledevice/libplist,libimobiledevice-win32/libplist,libimobiledevice/libplist,libimobiledevice-win32/libplist,libimobiledevice/libplist,Tatsh/libplist,libimobiledevice-win32/libplist,Tatsh/libplist,libimobiledevice-win32/libplist,Tatsh/libplist,Tatsh/libplist