[Lazarus] Mantis patch "Mouse-wheel-horz-scroll support"

[Alexey]

https://bugs.freepascal.org/view.php?id=32753

1. It is tested on Gtk2 and Win32. Gtk1 is not tested [but code is copy 
pasted, 4..5 values for vert scroll - copied block with 6..7 values for 
horz scroll, 6..7 is from gtk doc].

2. Maybe change issue section to "Patches"

3. you applied micro patch for LM_MouseHWHeel - changed in mantis patch


-- 
Regards,
Alexey