@FeatureDescriptor(name = FEATURE_USER_SUPPLIED_IDS)
            default boolean supportsUserSuppliedIds() {
                return true;
            }
Determines if an {@link Element} can have a user defined identifier.  Implementations that do not support
this feature will be expected to auto-generate unique identifiers.  In other words, if the {@link Graph}
allows {@code graph.addVertex(id,x)} to work and thus set the identifier of the newly added
{@link Vertex} to the value of {@code x} then this feature should return true.  In this case, {@code x}
is assumed to be an identifier data type that the {@link Graph} will accept.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/structure/Graph.java