Install a new compressor
A brand new event compressor based on Kuba Ober's cleverly simple
solution: <https://stackoverflow.com/a/
21006207>.
Fix #9362, #9461, #9933: Lyx suddenly gets keyboard keys wrong, and
deadlocks
Fix #9790: LyX should perform key event compression (for improving the
remote X connections one would also need to implement
Qt::WA_KeyCompression)
Fix #10516: slowness on repeated arrow keys with IBus and Qt5
Patch pulled from
https://github.com/gadmm/lyx-unstable/commit/
bf5a1efb0db5bfc2b
Signed-off-by: Juergen Spitzmueller <spitz@lyx.org>