Added Gitter badge
Merge pull request #40 from gitter-badger/gitter-badge

Add a Gitter chat badge to README.md
Allow injection of an explicit supervisor class.  This allows us to extend the RubyDNS::RuleBasedServer which amounts to allowing us to extend the DSL.
Add spec to test supervisor class injection.
Merge pull request #41 from dmarcked/feature/allow_class_injection

Make the Supervisor class injectable
Fix whitespace, namespacing.
Bump version.