Add sunlight/lightmap merging by multiply (r_sunlightMode 1)

Merge additive sunlight and map lighting into one GLSL shader (r_sunlightMode 2)
Change single lightmap blends to use lightall

code/renderergl2/tr_local.h

@@ -790,6 +790,11 @@ typedef enum
 	UNIFORM_AUTOEXPOSUREMINMAX,
 	UNIFORM_TONEMINAVGMAXLINEAR,
 
+	UNIFORM_PRIMARYLIGHTORIGIN,
+	UNIFORM_PRIMARYLIGHTCOLOR,
+	UNIFORM_PRIMARYLIGHTAMBIENT,
+	UNIFORM_PRIMARYLIGHTRADIUS,
+
 	UNIFORM_COUNT
 } uniform_t;
 
@@ -1969,6 +1974,7 @@ extern  cvar_t  *r_forceSun;
 extern  cvar_t  *r_forceSunMapLightScale;
 extern  cvar_t  *r_forceSunLightScale;
 extern  cvar_t  *r_forceSunAmbientScale;
+extern  cvar_t  *r_sunlightMode;
 extern  cvar_t  *r_drawSunRays;
 extern  cvar_t  *r_sunShadows;
 extern  cvar_t  *r_shadowFilter;