function Resultset(collection, options) {
      options = options || {};

      // retain reference to collection we are querying against
      this.collection = collection;
      this.filteredrows = [];
      this.filterInitialized = false;

      return this;
    }
Resultset class allowing chainable queries.  Intended to be instanced internally.
   Collection.find(), Collection.where(), and Collection.chain() instantiate this.

@example
   mycollection.chain()
     .find({ 'doors' : 4 })
     .where(function(obj) { return obj.name === 'Toyota' })
     .data();

@constructor Resultset
@param {Collection} collection - The collection which this Resultset will query against.