Add option to include space sensitive sorting

This doesn't seem like something you would want, but some users use spaces to manually sort items atop of lists. This would make that sort space sensitive and treat a space like any other non alphanumeric character and sort to the top.

 I am not familiar with qunit or I would have written a spec initially. If a spec is expected for the PR to be merged, then I will need a little more time to figure it out. 

Thanks for all the work you've done!!