Follows what we’re doing with the folders stuff. Avoids having too many
very straightforward methods on the model. Especially when the data they
need is only used by the form. So it’s better to encapsulate the logic
in the form.
Done using isort[1], with the following command:
```
isort -rc ./app ./tests
```
Adds linting to the `run_tests.sh` script to stop badly-sorted imports
getting re-introduced.
Chosen style is ‘Vertical Hanging Indent’ with trailing commas, because
I think it gives the cleanest diffs, eg:
```
from third_party import (
lib1,
lib2,
lib3,
lib4,
)
```
1. https://pypi.python.org/pypi/isort
When you make a ‘normal’ API key it won’t work as described until your
serivce is live.
We should make this clear at the point at which you choose this key.
