support case insensitive filtering

Using the Einstein example, if I filter by title for "curved" I get no results, but if I use capital C as in "Curved" I get the one result. You can see that in this fiddle. Change "curved" to "Curved" near the end of the script tag and click Run to get a result.

https://jsfiddle.net/5hp6gc1f/9/

I thought maybe I could do this by supplying "i" in a regex expression, but I couldn't figure out the syntax.