Fixed bad sample code in docs
Fixed bad sample code in docs

vertexIdKey was removed a long long time ago. Can't even find where it was last in the API going back to 3.0.x - that's been bad a long time...dah CTR

artem-aliev/tinkerpop,apache/tinkerpop,apache/tinkerpop,robertdale/tinkerpop,apache/incubator-tinkerpop,krlohnes/tinkerpop,robertdale/tinkerpop,robertdale/tinkerpop,apache/tinkerpop,artem-aliev/tinkerpop,pluradj/incubator-tinkerpop,krlohnes/tinkerpop,jorgebay/tinkerpop,krlohnes/tinkerpop,jorgebay/tinkerpop,apache/tinkerpop,apache/tinkerpop,robertdale/tinkerpop,apache/tinkerpop,robertdale/tinkerpop,jorgebay/tinkerpop,pluradj/incubator-tinkerpop,apache/incubator-tinkerpop,pluradj/incubator-tinkerpop,artem-aliev/tinkerpop,krlohnes/tinkerpop,jorgebay/tinkerpop,apache/tinkerpop,apache/incubator-tinkerpop,artem-aliev/tinkerpop,artem-aliev/tinkerpop,krlohnes/tinkerpop