Use more comprehensive hostname regex pattern Fix
Use more comprehensive hostname regex pattern Fix

I fix [this](https://github.com/jbenet/go-is-domain/pull/3) pull request. 
I hope you will accept it. I use the Cyrillic domain.

Sourced from http://stackoverflow.com/a/3824105

The current regex has issues with DNS names with multiple -s in them,
which happens with IDNs with Punycode. Also doesn't follow the RfC limit
of 63 octets per label.

User gfdfgh reported this on #ipfs
jbenet/go-is-domain,jbenet/go-is-domain