Present selectable list of versions to choose from #58

This proposal suggests to present a list of installable versions available if nodebrew is executed with zero arguments (yes, a change from the current behavior that simply shows help). In this case, nodebrew would present a list similar to the list presented from nodebrew list (or nodebrew ls), only the user could arrow up and down (or use j & k) to select the desired version. Upon the user hitting Enter on the currently selected version, the behavior would be identical to nodebrew use <version>. Bonus points for adding an entry called remote that fetches the list of versions that nodebrew ls-remote does and making those selectable, too! :)

See video of n's feature of this at https://github.com/tj/n (direct link to video is https://github.com/proxy/camo.githubusercontent.com/66e762002c2453c4756494f8dc4dea8a6665f240/68747470733a2f2f692e636c6f756475702e636f6d2f353963413856454461652e676966)