155 test fix

This fixes a few issues with the tests after pull #155.

1. test_settings didn't have SERVER_NAME. so i set that to 'localhost' and that fixes the "oh my goodness! what's my name!? i have no idea!? i'm freaking out!" test failure
2. the gravatar_url test failed because when it was written, it was using a fake flask app. @jezdez fixed that so it was using the standup app. i fixed it back to the fake flask app and also changed the email addresses to `example.com` addresses and fixed the results accordingly
3. one of @jezdez's tests creates a `r1cky` user, but didn't specify the slug. so i fixed the `user` model maker to create a correct slug if it's not specified, but also fixed the test to specify the slug it later uses
4. then i printed the entire diff out, burned it, used the ash to make soap, took a shower, got real clean and created this pr

I think this covers everything!

r?