Math Lib

* Convert all code to use new functions.
* Branch maintainers may want to skip this commit, and run this
  conversion script instead, if they use a lot of math functions
  in new code:
  http://www.pasteall.org/9052/python

source/blender/editors/interface/interface_widgets.c

@@ -35,7 +35,7 @@
 #include "DNA_userdef_types.h"
 #include "DNA_windowmanager_types.h"
 
-#include "BLI_arithb.h"
+#include "BLI_math.h"
 #include "BLI_listbase.h"
 #include "BLI_rect.h"