Log formats and general improvements

[initstring]

This PR will try to help those working with tooling output programmatically.

It gets rid of the old printc function and replaces it with fmt_output. This consumes findings as python dictionaries, giving us flexibility in how we deal with the data.

It behaves the same in terms of printing to the screen. However, when a log file is specified it can write the individual items to it either in CSV or JSON.

Still to do:

• Add a severity value (probably based on public exposure)
• Update the deb package manpage stuff
• Tag a new version after merging

Ideas from: #46

UPDATE:

I'm taking the time to address some other things in this PR, too:

• Lots of linting
• Some additional error checks
• Dealing with some edge-case DNS failures
• More accurate reporting of GCP AppEngine when behind auth

[prryplatypus]

To avoid breaking changes (unless you don't mind), maybe it's worth making this default to None and if that's the case then save the output in the current, existing format?

[initstring]

Hmmm, good point. I'm not so concerned about breaking what was already a hard to parse log file. But perhaps it's worth adding a "text" option as the default that logs it as plain text, without the ansi stuff. Some might be more familiar with that.

[initstring]

Done!