To be loaded toward top of doc (I know it's not best practice, but can help protect from FOUC)

2.1.4 - Trident/Compatability tweak for IE
2.1.3 - Trident/Compatability check for IE
2.2.0 - Safari Bug Fix, Trident Compat Update, *Nix OS update
2.5.0 - Device type dropped, ppi mod, check for framed in added
2.5.1 - Dropped OS check. Added ie-compat class.
2.5.2 - Added Chrome Frame check.
2.5.3 - Added OS check back. Checking for Win 8 Live Tile Mode and Surface.
2.6.0 - Added MS Viewport Fix, Removed Chrome Frame (since they dropped support)