DSUtil: Cosmetics.
Avoid the OSD flashing when skipping to a chapter.

The OSD displayed the seek message before it was immediately replaced by the chapter information.
Use elapsed/remaining time for the chapter change OSD depending on what is selected.

This commit fixes #1555.
AppSettings: migrate only present keys
Cosmetics in CAppSettings::UpdateSettings()
Fixes to reset settings option

 - Reset .ini now doesn't write ExePath to the registry
 - Reset .ini is now achieved through file write not delete

Fixes #3591
Rewrite mouse handling code (incomplete)

Fixes #1300, #1556, #2081, #3284, #3379

Also:
 - adds timer wrapper objects in MainFrm
 - hidden menubar is now acting like on-demand floating one
 - adds codepath for hiding toolbars in windowed mode,
   but no corresponding settings entries
 - TODO: option to autohide _all_ panels like toolbars
MainFrm: remove unused variable
D3DFS: remove horizontal margin from osd posbar

The bug with autohiding is now fixed and there's no reason to have it
there
ChildView: remove unneeded critical section
PlayerNavigationDialog: minor refactoring
PlayerListCtrl: call CWnd::OnTimer() in OnTimer()

Some mfc timers need that
Delay OnIdle() calls initiated by WM_MOUSEMOVE
Updated fullscreen property page

Will be squashed