Added .DS_Store to .gitignore
Resolved some (not yet all) broken references, removed unused imports, and separated multiple statements in single lines to multiple lines.
Replaced deprecated Python constructs (like has_key and the old form of raise) with current forms.
Fixed remaining broken references and updated deprecated Python constructs.
Zope2 DA was already almost PEP8 compliant; made the few more changes required to make it completely compliant.
Removed errant has_key.
Minor packaging updates to reflect changes.