1.0.36.34: WHO-CALLS information for source transformed calls

1.0.36.34: WHO-CALLS information for source transformed calls

 * Generalize the solution used for macroexpansion XREFs to take care
   of other source-level stuff: this includes both source-transforms
   and compiler-macros.

 Fixes launchpad bug #542174.

 Note re. 1.0.36.33: the commit message is erronous. The real commit
 message would have noted that since FIND-OPTIONAL-DISPATCH-TYPES
 doesn't rightly consider &REST mismatch a lossage in the presence of
 &KEY, we need to make sure the type assigned to the leaf has a &REST
 type if the function actually has a &REST argument.