-Clean up r_data.cpp and move colormap related functions to v_colormap.cpp.
-Move colormap related functions from v_palette.cpp to v_colormap.cpp.
-Add a new function V_GammaCorrect which performs gamma correction on an ARGB buffer.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4450 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Change V_BuildDefaultColorAndShademap to use a modified version of the RF_BuildLights algorithm, which can now support level.fadeto to generate colormaps that fade to colors besides black. This matches vanilla Doom better than the ZDoom 1.22 colormap generating code.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4451 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Add light color and fading color parameters to V_BuildDefaultColorAndShademap.
-Replace BuildColoredLights with V_BuildDefaultColorAndShademap.
-Fix a memory leak in GetSpecialLights.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4452 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Make gamma table static to v_palette.cpp.
-Change use of the gamma table to use V_GammaCorrect.
-Rename GetDefaultPalette to V_GetDefaultPalette.
-Rename GammaAdjustPalettes to V_GammaAdjustPalettes.
-Remove several unused functions from v_palette.cpp

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4453 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Axe the ZDoom 1.22 multiple palette handling code since it is unused.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4454 b0bcef46-2027-0410-bd56-ab726e9a1d04