Highlight cell text that matches the filter expression

Create a new binding, say "highlightedText" (e.g. data-bind="highlightedText: name"), that outputs the text of the field with a span.highlighted around the portion that was matched by the filter expression.

This will give visual feedback about which portions of each row were matched when searching.

Depending on implementation, this could be it's own separate project, just used in this one.
