Case insensitive searching in DataTables

Feature request from https://groups.google.com/d/msgid/shiny-discuss/528c4c7f-0fd3-4dbe-9a9c-bdb2018ed229%40googlegroups.com
Is it possible for `caseInsensitive` to not be present in `q$search`? In that case, `ci` would be `logical(0)`.

The same question applies to other parameters from `q$search`.