Check whitelists before checking DNS

This change is a slight performance improvement, as well as a bug
fix for the case where an IP address is in the whitelist.  Basically,
the whitelist should always be checked before any run of DNS queries.
Merge branch 'v2.1.4-lookup_rdns.strict' into v2.2.8-godsflaw
Merge branch 'v2.2.8-godsflaw'

Conflicts:
	plugins/lookup_rdns.strict.js
Merge remote-tracking branch 'upstream/master'
Merge pull request #440 from godsflaw/master

Check whitelists before checking DNS