Add new template for packages describing a content type
Clean up add on template

- Remove all stuff related with a content type creation (this is being covered with the new contenttype template)
- Rename upgrade step from 2000 to 1010
Clean up theme template

- Rename upgrade step from 2000 to 1010
- Clean up CI configuration
Avoid "AttributeError: 'NoneType' object has no attribute 'location'"

See: https://stackoverflow.com/questions/14801416/zc-buildout-stopped-working-importerror-no-module-named-apport-fileutils