Updating Xcode iOS foundation template for new launch image scheme, deployment target iOS 6
Renamed PolyLine -> PolyLineT to match other templated class naming schemes. Added typedefs for PolyLine2, PolyLine3, PolyLine3f, and PolyLine3d.
Merge pull request #620 from richardeakin/polyline_t

Rename PolyLine -> PolyLineT, add more typedefs.
Fixing #623, gl createSharedContext failing to restore current context thread local
Fixing failed multi-window Context sharing on MSW
Merge remote-tracking branch 'origin/glNext_ios_launchImages' into glNext
Merge remote-tracking branch 'origin/glNext' into glNext