Refactoring link_symbols into utils.cpp
Major refactorings in py's.

- Unified core compiler and mm compiler: shared classes are in
 pyutils.entries; opcode.py moved to pyutils.

- Changed meme_tr grammar to also support object declaration.

- Major change in core binary format:
  * all objects in the object table have a frame header containing:
    (a) a high-level type tag (regular, list, dict, string)
    (b) the total size in bytes for the object

  * Also, we are exporting less names (only the necessary/prime
    ones). Before, we were exporting all explicit and implicit declared
    objects, but doing that in the new code will be more troublesome,
    and since this isn't needed (it was to make coredump easier), I'll
    leave at that.

- Added a grammar to parse core files in "Synalyze It! Pro" app.