wtforms 3.0 is incompatible with our code. A separate issue will be
filed to address the incompatibilities, but this should be enough to get
working images out of it.
With 3.x, we're seeing:
```
File "/home/horazont/Projects/python/snikket-web-portal/snikket_web/main.py", line 35, in LoginForm
address = wtforms.TextField(
AttributeError: module 'wtforms' has no attribute 'TextField'
```
and the portal fails to start.
This reverts commit 486596f89f.
It was discovered that multipart/form-data forms do not work
correctly with Quart 0.15. The upgrade to Quart 0.15 was rushed
and not tested correctly, which I apologize for.
See-Also: https://github.com/pgjones/quart/issues/126
snikket_web can now be fully configured via the environment alone,
no extra files needed. It is still supported to inject a python
file to generate environment variables though, which may be
useful for generating and reloading a secret key.
