The better implementation of a224297.
Fixes ability to reorder tag aliases, especially - the ability to change
the tag's primary name after it was created. Until now, both of these
scenarios needed sad workarounds on the user part.
Ignored only the rules about continuing / hanging indentation.
Also, added __init__.py to tests so that pylint discovers them. (I don't
buy pytest's BS about installing your package.)
Post notes had mixed up column types. I fixed that and at the same time,
I took the opportunity to convert everything into Unicode. Also, I've
changed existing migrations rather than creating new ones - it's not
like we're even close to alpha...
rr-