Addresses issues with changing between A, AAAA and CNAME records in
both directions with the Cloudflare API

See also: github/octodns#507
See also: github/octodns#586
See also: github/octodns#587

Many providers make their modifications in the order that changes comes. In
python3 this causes things to be inconsistently ordered. That mostly works, but
could result in hidenbugs (e.g. Route53Provider's batching could be completely
different based on the order it sees changes.) Sorting changes consistently
is a good thing and it shouldn't hurt situations where providers are already
doing their own ordering. All-in-all more consistent is better and we have to be
explicit with python 3.

* spelling: ancillary
* spelling: antarctica
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This change hit a line length limitation, so I'm wrapping it and
adding a period which appears to match local style...

* spelling: quicker
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* spelling: zone

This change imports records that are marked as proxied so that they can be synced to other DNS providers as described in
[this support acticle](https://support.cloudflare.com/hc/en-us/articles/115000830351-How-to-configure-DNS-for-CNAME-partial-setup-when-managing-DNS-externally).
Records that use this functionality will be ignored by this provider and not be synced back to Cloudflare as we don't know the origin record values that would be required.

This change does not allow you to enable, disable or configure the CDN itself as that would require a lot of metadata to be handled by OctoDNS.
The intention of this change is to allow users to run a multi-DNS provider setup without sending any traffic to their origin directly.

See also github/octodns#45

Translates them to/from root CNAME

Before, 1-2k record took ~10s and more than that was just painful, 5k took
forever. This records things to keep a dict of nodes with a set of records so
that we can quickly "jump" to the point we're looking for without having to
search. 10k records now takes ~5s.