This is a preparatory commit for using isort for sorting all of our
imports, merging changes to files where we can easily review the
changes as something we're happy with.
These are also files with relatively little active development, which
means we don't expect much merge conflict risk from these changes.
Now reading API keys from a user is done with the get_api_key wrapper
method, rather than directly fetching it from the user object.
Also, every place where an action should be done for each API key is now
using get_all_api_keys. This method returns for the moment a single-item
list, containing the specified user's API key.
This commit is the first step towards allowing users have multiple API
keys.