Small material assigning feature:

in EditButtons, panel "Links and Materials", there's now a browse button
to directly assign a material to selected faces. It does:

- check if material was already in one of the 'slots' of the object
- if so, then use this as index to assign
- if not, then add a new slot, and assign the new index

source/blender/include/butspace.h

@@ -370,6 +370,7 @@ void curvemap_buttons(struct uiBlock *block, struct CurveMapping *cumap, char la
 #define B_DOCENTER		2015
 #define B_DOCENTERNEW		2016
 #define B_DOCENTERCURSOR	2017
+#define B_MATASS_BROWSE	2018
 
 	/* 20 values! */
 #define B_OBLAY			2019
@@ -381,6 +382,7 @@ void curvemap_buttons(struct uiBlock *block, struct CurveMapping *cumap, char la
 #define B_PREVKEY		2045
 #define B_NEXTKEY		2046
 #define B_LOCKKEY		2047
+#define B_MATCOL2		2048
 
 #define B_MESHBUTS		2090