User can create Team

* A signed in user with no team can create one
Here's the unofficial rule for newlines in tests. There should be (up to) four blocks of code, separated by newlines:

* Setup (defining variables, ...)
* The thing getting tested (signing in, going to a page, clicking a link, filling out a form, ...)
* The test (`expect` something(s) to be the case)
* Teardown/cleanup (usually there's not any of this)

This "newline after every line" business you've got going on in here is harder to read.