Task list for completing PIRC

[plobsing]

Originally reported in parrot TT #12 (http://trac.parrot.org/parrot/ticket/12)

Task list can be found in compilers/pirc/TODO, and includes:

1. Emit the actual bytecodes into a PackFile/codesegment.
   DONE.
2. Create a PMC constant for strings, numbers, keys and
   subroutines.
   Strings, numbers and subs are stored.
   DONE.
3. Complete PASM output, so it can actually be parsed and run.
   TODO
4. Handle :multi flag properly.
   DONE.
5. Handle nested macro expansions.
   TODO
6. Fix all memory leaks. this should be trivial, given PIR's built-in
   allocated-memory-pointer-registering infrastructure. In some
   places this is not used yet, and in others, it's not necessary
   to use it (but in those mem_sys_free() must be called explicitly).
   TODO
7. Figure out how :named argument passing works in bytecode.
   DONE.
8. Finish the parrot calling conventions ops in the back-end
   (var.args must be fixed).
   DONE.

This is a tracking ticket.