The old option descriptions were all written at different times, and needed some consistency. This makes everything consistent between the help text, README, man page, and shell completions, and fixes some mistakes made when writing them.
This also adds the missing options to the man page, fixing #175.
See #97 and recently #130 too.
This allows the user to pass in options such as "--ignore '*.pyc'" to not list any files ending in '.pyc' in the output. It uses the Rust glob crate and currently does a simple split on pipe, without any escaping, so it’s not really *complete*, but is at least something.
The original options was becoming a bit unwieldy, and would have been even more so if I added the same amount of comments. So this commit splits it up.
There's no extra hiding going on here, or rearranging things within the module: (almost) everything now has to be marked 'pub' to let other sub-modules in the new options module to see it.
