[BUGFIX] #90 locateByLayer doe not well cleaning input and map with joins

The feature locateByLayer does not well cleaning input and map when the layer has vector joins.

With it, we can add that:
* locateByLayer only use the first vectorjoins
* cascading filtering is not well done
* filtering based on a vectorjoisn and a field are not compatible
* multi-filtering on a same layer cannot be done

Signed-off-by: rldhont <rldhont@gmail.com>