Fix scopePath on Windows

[mikkotikkanen]

On windows the provided path slashes are "" instead of "/"

[jstroem]

Shouldn't this bug be fixed using: http://nodejs.org/api/path.html#path_path_sep

[mikkotikkanen]

Well, it doesn't particularly matter. ""-slashes break the regexp regardless.

[pmoleri]

I think the code shouldn't be using path at all, it's only using it to join dropbox paths instead of local paths.
I would use a simple string join: var scopePath = scope[0] === "/" ? scope : "/" + scope;

[CrackerakiUA]

why this is not merged?