Sort AAE differences before acting upon them via read-repair
Address review comments

The only Dialyzer differences between the base of the branch
and the tip is the line numbers for the complaints that
are present.
Fix a few dialyzer complaints
Remove hashtree:compare/2 and hashtree:compare/3 functions.

These functions are only used by tests and by developer
scaffolding.  See also:
https://github.com/basho/riak_kv/pull/646#discussion_r6673687
Derp, there's a hashtree_eqc.erl
Merge branch 'slf-aae-sort-difflist' into develop

Conflicts:
	src/hashtree.erl
	test/hashtree_eqc.erl