[MLton] Option to show path map

[Vesa Karvonen]

Quoting Stephen Weeks <sweeks at sweeks.com>:
[...]
> Or perhaps keep show-{anns,path-map} and change
> -show-{basis,def-use} to -save or -write?  I often get confused by the
> name "show" and I know others do too.

I'd vote for -save-{basis,def-use}.  As -show-{anns,path-map} are mutually
exclusive (the first one exits), it might be better to have a single option

  -show {anns|path-map}

for example.

-Vesa Karvonen