Fixes glob to work with 2.0.0

homesick list fails on ruby 2.0.0-rc2, I think because they fixed this
bug: https://bugs.ruby-lang.org/issues/6977, changing the way recursive
globs work. Test case:

```ruby
require "homesick"
require "pathname"

repos = Homesick.new.send :repos_dir

Dir.glob("#{repos}/**/*/.git") # => []

Dir.glob("#{repos}/**/*/.git", File::FNM_DOTMATCH) # => ["/home/eric/.homesick/repos/dotfiles/.git"]

```
This change, however, then broke 1.9.3, but removing the extra "/*"
works on both 1.9 and 2.0.

Your spec for `homesick list` fails on 2.0, and passes with my change, so it was not necessary to write an additional test.