Update references to web home

Remove URLs that point to now-defunct Google code site. Use GitHub for
lack of an obvious alternative.
Update versioning and metadata for possible release
Ignore distutils and py3k droppings
Update Debian packaging for consistency
Remove reference to missing issue
Fix typo
Describe key generation alternative
Merge pull request #3 from neirbowj/0.4.0-prerelease

Perpare patches for 0.4.0 prerelease