even the baseline supports glx 1.3

We won't support glx < 1.3!!!!

Change-Id: Icc5d15d682223b1fab3165d279b596446c920e9b
split the windows and linux intialization bits

This makes it much esier now to simplify the Linux selection logic.

Change-Id: I7db0daf81b1c9047d4ef95527c7b51c09e6ab80a
create symbols for glew in the debug case

Change-Id: Ia40d4477344f9fc0f9942a9d942b97a416ff11d7
make multisampling available on linux if available

This also greatly reduces the complexity of the OpenGL initialization on
Linux. We now require a RGBA framebuffer with 8 bits per channeland 24
bit depth.

Change-Id: I12d4bd6c15cbf95c6211c7af6a81ffbb228f05be
extract ugly function pointer initialization

Change-Id: I4bce735da5f4d9f9b3aaae92ec0cce6725f2016d
fix windows

Change-Id: I6ca5967fd84851bb2ee5af1325b70a6a5e160644