R509 option for subject alternate name

Hello

I'm working through the code to add subject alt names to the cli.
Reworked the bin/r509 so I could understand it a little better.

The specs are failing for me on master (mostly EC). It might be due to openssl 1.0.1e. Thought, I think EC is kinda out after all the press and the NSA. Pushing this in to see what travis says.

Thanks for the code.