Intermediate directories in log path structure should be created if not present

[lwoodson]

When I configure gumshoe to log into a file in a nested directory structure like this...

Gumshoe.configure(new SimpleConfiguration("my-app", "logs/gumshoe/gumshoe.log"));

An exception bubbles up if any of the directories are missing (logs or gumshoe). Gumshoe should create these directories if they do not exist.

[benchai]

A useful feature to logging it to have different levels of logging verbosity.

It would be nice to be able to have debug logs that list really verbose things like maybe the state of all variables in scope, but at the same time when going through logs normally those should be hidden.

[lwoodson]

Thanks @benchai. Can you create that as a top-level item? i.e. a separate issue from this one.