Add installation instructions.

...because someone else will forget to do this too.
Add templatetags package.
Merge commit '2e8a94de06204926458c1da9f21bb21e03079cfe'

* commit '2e8a94de06204926458c1da9f21bb21e03079cfe':
  Add templatetags package.
Merge pull request #7 from schinckel/master

Add installation instructions.
Fix packaging