- moved libOSMesa.a to -static as it's usable only with non-dri libGL.a
- build usable shared libOSMesa
- updated License tags
- fixed ffb disabling if building without nouveau
- package gl,glu pkgconfig files
- xmesa*.h headers (with x11 non-dri Mesa API) moved to libGL-static
- dropped glfbdev.h header (fbdev Mesa API - no implementation built)
- test release 3.1