File glob matching

So you'll notice because most people will tend to write `*.foo` when using a glob instead of `foo` just referring to the extension that the equivalent glob will generally win. And if it doesn't win, then it is equal length anyway (like `Gruntfile` as both the extension and the glob). There may be more edge cases that I'm not thinking about right now ... but this was my general idea.

Applies to atom/first-mate#17