Refactored #get_ruleset to be part of RubyDNS.
All database logic should be inside RubyDNS since BeEF's DNS class
is mostly just a wrapper around it.
Implemented POST handler for /api/dns/rule which adds a new rule.
A host of other changes got roped into this as well. #match now
silently handles blocks passed as a String in order to handle
the 'block' JSON parameter. This is because sourcify doesn't
work with eval'd data.

Rule id's are no longer incremental integers. It's now a 7-character
"token" generated from #secure_token and is managed by the RubyDNS
module.