spamassassin: 13 new tests. Moved config loading

into register() with callback

remaining changes are to improve testability
Merge pull request #667 from msimerson/spamassassin

spamassassin: 13 new tests. Moved config loading
cleanups: remove docs for deprecated plugins
TODO -> done.
rm plugins/connect.rdns_access
remove relay_acl tests
codeclimate: karma updates
tests/helo.checks, cleanups
added codeclimate image to README.md
t/helo: replaced 'var outer' with bind(this)
helo.checks: consolidated two tests into one

less duplication