Support running subcommands as distinct binaries.
Pass arguments to subcommands.
Improve use of BIN_NAME variable.
Improve check for subcommands.
Add `fresh commands` to drive completions
Add completions for subcommands
Add subcommand documentation to the README
Make use of `fresh commands` in `fresh help`
Improve error message when a command is not found
Add tests for subcommands
Tweak subcommands heading in the README
Merge pull request #53 from freshshell/subcommands

Support for subcommands as distinct binaries