Update documentation of command line options and parameters

[martinheidegger]

There are a few things undocumented. For example:

--no-color option and lang-list or completed to get the completed commands. Since the translation should be be added for all language I keep this as an open issue. Particularly since I plan to add a few more commands.

[martinheidegger]

New command line option credits is active when a the package.json contains a list of contributors