Blender icons now are in the 21st century too!

Default size for bitmap now is 32x32 pixels. Code change for higher densities is easy,
all under review. Let's first check this!

source/blender/editors/interface/interface_icons.c

@@ -81,9 +81,9 @@
 #define ICON_GRID_COLS      26
 #define ICON_GRID_ROWS      30
 
-#define ICON_GRID_MARGIN    5
-#define ICON_GRID_W         16
-#define ICON_GRID_H         16
+#define ICON_GRID_MARGIN    10
+#define ICON_GRID_W         32
+#define ICON_GRID_H         32
 
 typedef struct IconImage {
 	int w;