Add "View Selected" (numpad .-key) for faceselect mode and the uv editor.

Also includes some 2d vector operations (subtract, dot, normalise).

source/blender/include/BDR_editface.h

@@ -47,6 +47,7 @@ void select_linked_tfaces(void);
 void deselectall_tface(void);
 void selectswap_tface(void);
 void rotate_uv_tface(void);
+void minmax_tface(float *min, float *max);
 int face_pick(struct Mesh *me, short x, short y);
 void face_select(void);
 void face_borderselect(void);