#232 Win32: Borderless window and mouse clipping

[Anonymous]

New features:
- creation of window without borders
- prevent mouse from escaping outside application window in windowed mode (borders or not)

Usage:
irr::SIrrlichtCreationParameters params;
params.WindowNoBorder = <true|false>; // default false
params.MouseClip = <true|false>; // default false

Tested and used a little, more extensive testing needed (though it seems to work well on My Testing Environment (tm)). Microsoft Windows only. Didn't have the time or resources to apply this on other platforms (is it even needed?).

[Anonymous]

patch-file created with linux diff for both described changes

[Anonymous]

Btw, this patch was made to 1.7.3.