-Move the templated pixel shader functions from doomtype.h to v_video.h.
-Replace a few uses of alphablend2a with the templated rt_blend2 to eliminate some code duplication in the screen wipes.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4442 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Remove alphablend2a as rt_blend2 replaces it.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4443 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Add v_colormap.h.
-Move the definition and implementation of shademap_t, shaderef_t, and translationref_t to v_colormap.h from their scattered locations in the source tree.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4444 b0bcef46-2027-0410-bd56-ab726e9a1d04