interim release 678

I've put out a new interim release 678.  I haven't worked on bugs for a
while so this one will probably be buggy.  I'm overdue for a real release so
I'll work on bugs next and a real release.

Differences between interim release 656 and this 678 ...

    Added Slice obj support with init_, str_, etc.
    getItem_, setItem_, del_item_ (obj[idx] equivalents) now support single
args, not just slices.
    Replaced print keyword with print() function
    Added function-as-command feature.  print is now backwards compatible.
    Changed "except Exception, var:" syntax to "except Exception as var:".
    Dictionary methods now check keys for immutable flag bit
    fparam_ attribute of func objects now fully introspectable
    Added Weakref object with object modification callback feature
    Removed return value of init_ replacing self feature
    Changed del_ method name to final_
    Added prop keyword and properties feature with get_, set_, and del_