Added totalCount config to Phalcon\Paginator\Adapter\QueryBuilder

[Izopi4a]

I guess situations like this https://forum.phalconphp.com/discussion/12207/how-to-alter-count-logic-in-querybuilderpaginator in some high complex application, are highly possible.

With this patch developers can specify the exact number of total results ( by performing a query of their own before that ) without build-ed in counter being fired.

Maybe another plus of this patch is sometimes people wants to count id, instead of *, with this patch they can do it the way they want without any dramatic changes to the framework itself.

//other ideas:
It can be done by checking if the given value is_numeric, otherwise people can specify raw queries, or pass another builder, but i think it might end up being an overkill.

example usage :

use Phalcon\Paginator\Adapter\QueryBuilder;

$paginator = new QueryBuilder(
    [
        'builder'    => $builder,
        'limit'      => 20,
        'page'       => $currentPage,
        'totalCount' => $counterQuery->execute()->total_rows
   ]
);