MainFrame: use timer pool for updating dvb info
MainFrame: use timer pool for resetting status
MainFrame: use const instead of static
MainFrame: more floating menu fixes
MainFrame: remove menu modal loop notification

It's no longer needed.
MainFrame: fix cursor hiding with system menu

Alt+Space combination wasn't liked much.
mhook: backport version 2.4 changes

Obsoletes one of our hacks.
Periodically flush .ini cache

Refs #4161