Merge branch 'master' of https://github.com/Sryder13/SRB2

Fixed flashes for OpenGL Nukes/Teleports etc.

Removes HOMs from OpenGL.
This also seems to have made skyboxes not draw ontop of everything else
on Intel GPU's.

Post processing no longer done in the skybox.

Pulled

change version number to 2.1.4, add linux64 info

Huge thanks to Alam_Squeeze from #srb2fun. :D

Fixes intermission pictures being taken in OpenGL.

Hopefully.

OpenGL Fixup

Fixed translucent midtextures being opaque when there were multiple
lights in a sector.

OpenGL skyboxes.
Slight change to sky vertical offsetting.

Fixed the stupid error I made that was causing software to not draw
cropped patches.

MD2's that replace mobjs that have a skin, but the skin doesn't have an
MD2 now display.

MD2's can be translucent again.
MD2's can use sprites instead of another random texture if they have no
texture.
Patches are drawn in the correct place on non aspect correct
resolutions.
Cropped Patches are drawn.