Cardinality resolves to VertexProperty$Cardinality on server

Reported on [janusgraph-users](https://groups.google.com/d/msg/janusgraph-users/sF16wXEZowY/nJNmWi2YDQAJ)

```
gremlin> JanusGraph.version()
==>0.3.0
gremlin> Cardinality
==>class org.janusgraph.core.Cardinality
gremlin> :remote connect tinkerpop.server conf/remote.yaml session
==>Configured localhost/127.0.0.1:8182
gremlin> :> Cardinality
==>class org.apache.tinkerpop.gremlin.structure.VertexProperty$Cardinality
```

It would be better if the class loading order was the same between a local Gremlin Console session vs scripts sent to a remote Gremlin Server. This behavior is new in 0.3.0 and does not appear in 0.2.1.

Compare `Cardinality` resolution in the local Gremlin Console with scripts sent through the remote connection configured by `conf/remote.yaml` to the localhost Gremlin Server. Trace the class-loading or script-evaluation entry points responsible for the differing results, and add regression coverage showing that both contexts resolve `org.janusgraph.core.Cardinality` consistently.

Written by the indexing model from the issue text.