3D View boarder/lasso select tool options

Add tool options to control how select operates (add/sub/set/and/xor).

Note: edit mode armature select still needs to support all options,
this is complicated by how it handles partial end-point selection.

source/blender/editors/space_node/node_select.c

@@ -45,6 +45,7 @@
 
 #include "ED_node.h"  /* own include */
 #include "ED_screen.h"
+#include "ED_select_utils.h"
 
 #include "RNA_access.h"
 #include "RNA_define.h"