Supporting - for dune init project

[saroupille]

Desired Behavior

At the moment, if one does:

dune init project foo-bar
dune: NAME argument: invalid component name `foo-bar'
      Library names must be non-empty and composed only of the
      following
      characters: 'A'..'Z', 'a'..'z', '_' or '0'..'9'.
Usage: dune init project [OPTION]… NAME [PATH]
Try 'dune init project --help' or 'dune --help' for more information.

but I believe it could succeed by using - for the public name and _ for the internal name.