Add project skeleton generation to `rust pkg`

[DylanLukes]

I think it'd be beneficial for getting new rust programmers up to speed to have something along the lines of npm create, that generates a simple project structure for a library or executable program, or both.

I'm entirely unfamiliar with what they're supposed to look like myself as of yet, and have been unable to find anything explaining it. If I knew, I'd implement this myself...

• Dylan

[metajack]

leiningen does this particularly well. It makes things from templates and can also look up template plugins from clojars, so that the templates don't have to be installed when you run it.

[emberian]

This should probably wait until rustpkg figures out how it wants to work.

[thestinger]

rustpkg is gone