MapServer updated to 4.6.2, Installer fixes finished

As promised: MapServer is updated to 4.6.2, and the version checking logic is fixed to work with Graphics Libs 2.0.

Also, the GIS Libs package for Tiger wasn’t really fixed. Or rather, Apple’s PackageMaker kept changing the authorization option on me. That’s fixed now, so you should download that again (I didn’t change the version).