Added alternative emoji set.

So basically, I wanted the ability to continue using GitHub, Campfire, etc with the shorthand without having TextExpander expand them in those apps. So I did a find-and-replace for `:` with `;`, so you can use the same shortcuts except using semicolons when you want them expanded immediately. 

Don't know if this is the kind of thing you'd want merged, but i thought I'd let you know.