Initial work for split out of s3control

[SimonToftegaard]

As discussed in #4707 here is the initial separate implementation of s3control

[bblommers]

Thanks @SimonToftegaard

[SimonToftegaard]

Seems like the unit tests in server mode do not get intercepted correctly by the mock_s3control, not sure how to fix this.

[bblommers]

One potential cause could be that the request is picked up by the S3-module, instead of S3control, because the regex for the S3-urls will still catch requests to s3control-urls. That's just a hunch though, I'd have look a little deeper into it to verify whether that's the case

[bblommers]

OK, found the issue - ServerMode tests will always fail for S3Control.
From the original tests:

# All tests for s3-control cannot be run under the server without a modification of the
# hosts file on your system. This is due to the fact that the URL to the host is in the form of:
# ACCOUNT_ID.s3-control.amazonaws.com <-- That Account ID part is the problem. If you want to
# make use of the moto server, update your hosts file for `THE_ACCOUNT_ID_FOR_MOTO.localhost`
# and this will work fine.

#4745 contains a clean implementation of this change, without any changes to the logic or tests. We will merge that one first, to ensure we're not breaking anything else.
After that we can have a look at extending the logic to allow other account ID's.