* pgenutil.pas: factor out the reading of generic specialization parameters (parse_generic_specialization_types) and the generation of a generic type name (generate_generic_name)
* pdecsub.pas, parse_proc_head:
    * also allow an interface alias declaration if an identifier is followed by a "<" (which starts a specialization)
    + add a procedure "consume_generic_interface" which parses such a specialization (by using "parse_generic_specialization_types") - this is needed, because "consume_generic_type_parameter" can (and should not!) handle "ISomeIntf<Integer, T>" or (somewhen in the future) "ISomeIntf<TSomeOtherGeneric<T>>" - and finds the correct symbol for the interface (by utilizing the "generate_generic_name" function)
    * generate the correct mapping entry (for the generic it's only needed for checking (if any), but for a specialization it's essential that we reference the correct specialization)

+ add tests which were included with the issue and also two additional ones

Note: In non-Delphi modes an interface alias can be done like in Delphi mode; "specialization" is not necessary and furthermore not even allowed!

git-svn-id: trunk@21656 -