Opendns Umbrella Module

It's been far too long since new modules were added to Hubot-VTR, so here's one: OpenDNS Umbrella!

Right now this supports 3 actions:

### hubot what's up with domain.com

This will give you a very quick 👍 or 👎 on a given domain address.

### hubot opendns rr ip

This will look up the domains OpenDNS has seen pointing at a specific IP address.

### hubot opendns secinfo domain.com

This will look up the security information OpenDNS has on a given domain including domain entropy, if it's an algorithm based domain, if it's blocked, etc.

There's a bunch of other integrations that could be done along these lines, but these are a good start I think.