Multiple calls in ICommandConverter.

Added support for multiple calls so search and count can be performed as one action from REST plugins.

Save result to specified header.

Getting ready for v1.1.2

TODO: think about using _ for command GET arguments which support in-argument objects.
More query features added.

Order for find. Use order=match in query parameters.
Exists and check methods. Return if objects were found or not.

Minor refactoring.
Random object initialization change.

Baked in serialization expects correct nullability which is lost in object is created using FormatterServices.GetUninitializedObject

Create new instance with empty ctor if it exists.