anchor.diff:  ==>sugar
   ==>utilities[active]
   gremlin> :plugin use sugar  <2>
  -==>...
   ==>sugar activated
   gremlin> :install com.tinkerpop neo4j-gremlin x.y.z  <3>
   ==>loaded: [com.tinkerpop, neo4j-gremlin, x.y.z]
  
positive.code: ==>utilities[active]
  ==>neo4j
  gremlin> :plugin use neo4j <5>
  ==>...
  ==>neo4j activated
  gremlin> :plugin list <6>
  ==>server[active]
  
negative.code: plugin activated: server
  plugin activated: utilities
  gremlin> :plugin use giraph
  ==>giraph activated
  gremlin> 
  ----
  