Add support for secure connections (https)

[vicb]

If the implementation is ok I can add:

• a test certificate,
• unit tests.

[luizmineo]

Thanks! It seems fine to me. It would be nice to have an example on how to setup a certificate with this API.

[vicb]

A wiki page ?

[vicb]

I can also add an https folder in the example folder with an ex.

[luizmineo]

Either one would be great! I was thinking of adding a new section here: https://github.com/luizmineo/redstone.dart/wiki/Server-Configuration

[vicb]

I'll update this section and add an example, most probably tomorrow.

[luizmineo]

No worries. Thanks again!