Unkown commands not detected

[Robert Audi]

When trying to execute an unknown command, tsm fails with an ugly message instead of showing the help.

Current behavior:

$ tsm foobar
__tsm::main:4: command not found: __tsm::commands::foobar

Expected behavior:

$ tsm foobar
[ERROR] !!! Command not found: foobar
Usage: tsm <command>

Commands:
  help          Show usage information
  copy          Copy a saved session
  remove        Remove a saved session
  restore       Restore a saved session
  resume        Restore and attach a saved session
  show          Show details about a session
  quit          Quit tmux
  list          List saved sessions
  version       Show version
  rename        Rename a saved session
  save          Save the current session

[Robert Audi]

Fixed in v0.1.4