Revised pointcut/1. Renamed pointcutdefinition-pointcut/2 to
pointcut-pointcutdefinition/2. New relations
aspect-pointcutdefinition+/2, aspect-pointcutdefinition+|exposed/2 (in
addition to the older aspect-pointcutdefinition/2) and friends.
Difference best illustrated on AJ-LMP-RefineUsedPointcut. 
Related to #6.