Add output format flag for easier parsing of results

[wumb0]

Add a parse-able output mode. nmap has the very nice -oG option that makes grep-able output. It would be nice if netexec had something similar instead of having to grep for Pwn3d and then awk-ing stuff out of the log output.

[Marshall-Hallenbeck]

@wumb0 How would you like the output? We had this discussion maybe a year ago and the way we do output/logging makes it hard, but I think it'd be fine to revisit this. If you have examples of other tools doing it that you like that'd be great.