Fixes preference file being reordered after each run.

Was flipping the order of preferences in the file after each save.
Turn down severity of bloom effect.
Keep track of whether or not we've turned on matrix attributes.

General improvements for number of OpenGL calls made;  remember whether
we've turned on matrix attributes, and don't bother re-setting those
states if they haven't changed.

This whole thing really needs to be improved;  probably will happen when
I get around to implementing real VAO support.
No implicit RenderTarget clears;  they must be requested explicitly.

Adds a "ClearRenderTarget()" command to vsDisplayList, which will cause
the currently set render target to be erased.
Add preference for MSAA antialiasing.

Defaults to false.