gui_toolkit 0.22.1

Added

• render.set_teardown_wait(r, ms): destroy waits at most that long for the swap chain (and a translucent window's DirectComposition objects) to be released, which happens on a thread of its own; past it the release goes on by itself. Releasing a swap chain waits for the system's compositor to let go of the window's surface, and on a machine whose cores are all busy that took seconds in a program that was closing. 0 (the default): destroy waits as long as it takes, as before.