Update CHANGELOG for python 3 work

CHANGELOG.md

@@ -1,8 +1,28 @@
 ## v0.9.9 - 2019-??-?? - Python 3.7 Support
 
-* Route53 _mod_keyer ordering wasn't complete/reliable and in python 3 this
-  resulted in randomness. This has been addressed and may result in value
-  reordering on next plan, no actual changes in behavior should occur.
+* Extensive pass through the whole codebase to support Python 3
+   * Tons of updates to replace `def __cmp__` with `__eq__` and friends to
+     preserve custom equality and ordering behaviors that are essential to
+     octoDNS's processes.
+   * Quite a few objects required the addition of `__eq__` and friends so that
+     they're sortable in Python 3 now that those things are more strict. A few
+     places this required jumping through hoops of sorts. Thankfully our tests
+     are pretty thorough and caught a lot of issues and hopefully the whole
+     plan, review, apply process will backstop that.
+   * Explicit ordering of changes by (name, type) to address inconsistent
+     ordering for a number of providers that just convert changes into API
+     calls as they come. Python 2 sets ordered consistently, Python 3 they do
+     not. https://github.com/github/octodns/pull/384/commits/7958233fccf9ea22d95e2fd06c48d7d0a4529e26
+   * Route53 _mod_keyer ordering wasn't 100% complete and thus unreliable and
+     random in Python 3. This has been addressed and may result in value
+     reordering on next plan, no actual changes in behavior should occur.
+   * `incf.countryutils` (in pypi) was last released in 2009 is not python 3
+     compatible (it's country data is also pretty stale.) `pycountry_convert`
+     appears to have the functionality required to replace its usage so it has
+     been removed as a dependency/requirement.
+   * Bunch of additional unit tests and supporting config to exercise new code
+     and verify things that were run into during the Python 3 work
+   * lots of `six`ing of things
 
 ## v0.9.8 - 2019-09-30 - One with no changes b/c PyPi description problems