Draw desktop windows before other windows

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>
Merge branch 'master' of github.com:mortehu/cantera-wm
Simplified keyboard grabbing code

XGrabKey needs a lot of arguments, and most of the were the same at every call,
so it made sense to create a wrapper function.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>
Corrected usage of XNextEvent and XFilterEvents

XNextEvent really returns void, and XFilterEvents is to be called on all
events, not just KeyPress.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>
Remove Ctrl-Alt-Q shortcut

This keyboard is too close to the Chromium exit shortcut, and too risky.
Ctrl-Alt-Backspace should be enough for everyone.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>
Add support for Alt-F4

Alt-F4 sends a WM_DELETE_WINDOW client message to the first window in the
active workspace.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>