filter

Is your feature request related to a problem? Please describe.
There are cases, when it might be useful to know how much points are there in index, which satisfies some filtering condition.
Currently, we can only estimate a total amount of points.

Describe the solution you'd like
Create an API which returns amount of points (estimated or precise, depending on flag) for a given filter

Describe the bug
I created a component in QueryBuilder.tsx by taking the example from the README with some little cleanup. It all worked except the CSS import causes an issue. Is there a solution that is supported in tsx or a hosted css file that can be used?

./node_modules/react-awesome-query-builder/lib/css/styles.css:1
.qb-drag-handler, .qb-draggable, .query-builder {
^

Synt