When in miscmodels, the config module was unable to find the function.
It appears to be some sort of circular import issue:
```
File "/home/rcorre/projects/contrib/qutebrowser/qutebrowser/app.py", line 44, in <module>
from qutebrowser.completion.models import miscmodels
File "/home/rcorre/projects/contrib/qutebrowser/qutebrowser/completion/models/miscmodels.py", line 24, in <module>
from qutebrowser.completion.models import completionmodel, listcategory, util
File "/home/rcorre/projects/contrib/qutebrowser/qutebrowser/completion/models/util.py", line 24, in <module>
from qutebrowser.config import config
File "/home/rcorre/projects/contrib/qutebrowser/qutebrowser/config/config.py", line 223, in <module>
class ConfigCommands:
File "/home/rcorre/projects/contrib/qutebrowser/qutebrowser/config/config.py", line 314, in ConfigCommands
@cmdutils.argument('command', completion=miscmodels.bind)
AttributeError: module 'qutebrowser.completion.models.miscmodels' has no attribute 'bind'
```
As configmodel imports util (and thereby config as well) it is unclear
to me why moving bind() to configmodel actually fixes this, but it does.