Fix user duplication tests.

The original tests could be passed if a uniqueness constraint was put
on the email address attribute instead of the name attribute.  These
modifications prevent that from being possible in the future.
Require 50 character names to be valid

If we don't add this test into the repository, then the maximum length
can be anything at all.  This simple test ensures 50 character user
names are acceptable, but 51 character user names are not.
Tests for displaying churches

These are simple tests to ensure that the full church list and
individual church listing exist and print minimal information out.