Updated shodan_search for new API

Updated to support new API, domain, and HTTPS.

Shodan has recently added new domains, new API, and everything
is now over HTTPS. Optional DB reporting has been update so it
can be used as input to RHOSTS for other modules.
the trailing '\' is ok and valid, but you can also just leave a trailing '+' instead.  Ruby interpreter will know there's more string on the next line.  Personally I prefer the '+', but that's just me and I don't think the Ruby style guide has an opinion on the matter.