dispatch: don't show list of commands on bogus command If a command is ambiguous, you get this: $ hg ve hg: command 've' is ambiguous: verify version [255] If you typo a command, you get this: $ hg comit hg: unknown command 'comit' (did you mean one of commit, incoming, mycommit?) [255] But if you completely mistype a command so it no longer looks like any existing commands, you get a full list of commands. That might be useful the first time you use Mercurial, but after that it's probably more annoying than help, especially if you have the pager enabled and have a short terminal. Let's instead give a short hint telling the user to run `hg help` for more help. Differential Revision: https://phab.mercurial-scm.org/D4024