Bins break when called from within a directory whose name has a space

[Jwashton]

Steps to reproduce:

1. mkdir My\ Stuff && cd My\ Stuff
2. Try to run irb, ruby, mix, or iex. On my system they all just sit on a blinking cursor.

I can run any of those commands from any path that doesn't have a space, as far as I can tell. Furthermore, running the bin directly seems to work. (i.e. ~/.asdf/installs/ruby/2.2.3/bin/irb)

Of course, my favorite option would be to avoid naming my directories with spaces, but I don't always have full say in the matter.

*Update I was originally trying this in Bash on Fedora 22. When I try the same thing from OS X, the screen will spam "usage: dirname path".

P.S. I've been quietly using asdf for about six months now, and love it! I don't have much experience with Bash programming, but if the cause of this doesn't seem immediately obvious to you I would be willing to try to track this down.

[Jwashton]

I found a fix, PR coming in a bit.