- add `binPaths` param

Lots of bugfixes here, we properly parse ranges and versions, and we
also now work with git repos and gists, and know when they are already
installed.

This will allow for a locally installed package to differ from the one
requested on the command line, the one requested will now actually run.

The workspace-location-msg file was being called improperly by `npm
init` and not even tested, and when digging in it probably shouldn't be
used at all from there. It's not always a workspace in this context.