Don't include unit tests in the package.

Unit tests were being included in the django-evolution package, causing
issues.

Fixes bug #134
Stop telling people to run --hint --execute.

There are times when --hint --execute is useful, but it's generally best
to save the hint and make it part of the proper evolution list. So, stop
telling people to run this, in order to prevent issues with their
database.
Include NEWS in the source tarball.

This makes life a bit easier for packagers and those checking out the
release through the source downloads.

Fixes bug #130