Bad Request in latest version when used with server-side classes, works in v0.5.13

[ErikBjare]

aw-client report $(hostname) gives requests.exceptions.HTTPError: 400 Client Error: BAD REQUEST for url: http://127.0.0.1:5600/api/0/query/ if I modify the code to use get_classes() which retrieves server-side settings. See #89.

Strangely, it works if I apply the same changes on the v0.5.13 commit.