#80 AcceleratorTable forgotten without a reference

[Kieron]

I need to go through some hoops to make AcceleratorTables work.
If I also store the AcceleratorTable reference in a separate variable which exists for as long as the window, it works.
If I don't, the window does not respond to any keypresses.

This may be a known problem (and perhaps why there is no "AddAcceleratorTable" method), but I feel it should at least be mentioned in the manual.

[Kieron]

Example code. Press "a" a few times to see the bug.