rpcrt4: Improve trace in RPCRT4_find_interface to print the interface identifier data as well as the object guid.

In particular, don't allow them after cpp_quote and without a statement.

Update the rules for importlib, library definition, dispinterface 
definition, interface definition, coclass definition and module 
definition to optionally allow a semicolon postfix.

Call pop_import from the parser instead of the lexer to ensure that 
pop_import is only called after the last statement in the imported file 
has been parsed.