Internal (WSF): Added Client-Supplier comments

* Clients: Added note for clients describing each form of client in a
short description.
* Suppliers: Added note for suppliers and how WSF_RESPONSE generally
uses each one.

NOTE: In any Eiffel class one has simple access to know who are the
clients and suppliers of the class. What becomes quickly lost is the
orientation and understanding data about why each relationship is there,
the purpose it serves in the grand scheme, and how it works (terse
descriptions). Getting this information out of the designers head and
into the class on a largely stable class or set of classes will help
completely new developers quickly orient and then understand the class
under examination and know how it fits with its fellows. Perhaps they
will even learn how to use the class as a problem solving tool!