Make io.arlas.server.utils.MapExplorer more generic

[sylvaingaudan]

The method public static Object getObjectFromPath(String path, Object source) is supposed to be generic. However it contains a specific block with a strong dependence on CollectionReferenceDescriptionProperty. Removing this block might have an impact on classes trying to access properties on CollectionReferenceDescriptionProperty.

Code to remove:

if (source instanceof CollectionReferenceDescriptionProperty
                    && ((CollectionReferenceDescriptionProperty) source).properties != null
                    && ((CollectionReferenceDescriptionProperty) source).properties.containsKey(pathLevels[0])) {
                return getObjectFromPath(newPath.toString(), ((CollectionReferenceDescriptionProperty) source).properties.get(pathLevels[0]));
            }