Fixed a small issue when building with scons on windows. If you have another version of mingw in PATH it would use that one instead. Also updated the a couple SWIG interfaces to handle simple output parameters as described in ticket 340.

{
	'opengl': ['core/video/opengl/', 'core/gui/base/opengl/'],
	'zip': ['core/vfs/zip/'],
	'script-python': ['swigwrappers/python'],
	'script-lua': ['swigwrappers/lua'],
}