fix/workaround [#34026] Blender starts with too large window

Minimal change to stop blender window opening across all monitors.

Workaround the problem by starting maximized, and using sane defaults for non maximized window.

I checked on a few different solutions to this, Using Xinerama works OK, but with different size monitors
and not knowing which one the window-manager will pick in advance - this can be wrong too.

Now instead of opening with the screen size, just start maximized and use a default size for the non-maximized window (clamped by the screen size).

This isn't perfect since you could have 2x monitors at 1024x768, open blender, un-maximize - and blender window would cross over into the second monitor.


git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@54220 954f8c5b-7b00-dc11-b283-0030488c597c