detect() should return all subfields for all keys, but with `none` or other null value.

[gregglind]

Because `info.get('browser',{}).get('name', 'unkown') is gross in python :)

This could be done as

1. module level 'config': 'complete=True'
2. An arg to detect(full=true) or (verbose=True)
3. Other / all of the above!

Holler if you like any of these / want a PR.