Fix WindowsGL project template : use the right Program Files folder and fix an issue with the resolving of assembly references finding the WindowsPhone ones before the Windows ones (error was MessageFilterHook type not found when launching a new WindowsGL project).
Fix assembly references for all project templates that were using MSBuildExtensionsPath instead of MSBuildProgramFiles32.
Merge pull request #2104 from speps/develop

Fix WindowsGL project template : use the right Program Files folder and ...