Help command now display nested subcommand help info e.g. archway help contracts new
Verified the default and required values being displayed.
Sorted required arguments at the start of arguments list. Separated required flags from the other flags, also separated transaction and keyring flags in a separate group.
Verified command examples
Removed index files on nested subcommands because it caused the help module to treat them as regular commands. The descriptions for them are added on package.json. Only downside is that this makes them not available for unit tests, those were removed
archway help contracts new
Closes #222