v1.0.4

Add regexp responders feature.

To register a regexp responder, see:

• RegisterResponder & MockTransport.RegisterResponder with url prefixed with "=~"
• new RegisterRegexpResponder & MockTransport.RegisterRegexpResponder

And to help writing custom responders, new functions:

• GetSubmatch & MustGetSubmatch
• GetSubmatchAsFloat & MustGetSubmatchAsFloat
• GetSubmatchAsInt & MustGetSubmatchAsInt
• GetSubmatchAsUint & MustGetSubmatchAsUint