anchor.diff:  |`writeGraph(String)` | Sets the path to a `GraphFactory` compatible configuration file for the target graph. | _none_
   |========================================
   
  +NOTE: `BulkLoaderVertexProgram` comes with a default `BulkLoader` implementation, namely `IncrementalBulkLoader`. It will work for the most use-cases, but has one limitation though: It doesn't support multi-valued properties. `IncrementalBulkLoader` will handle every property as a single-valued property. A custom `BulkLoader` implementation has to be used if the default behavior is not sufficient.
  +
   [[traversalvertexprogram]]
   TraversalVertexProgram
   ~~~~~~~~~~~~~~~~~~~~~~
  
positive.code: 
  [gremlin-groovy]
  ----
  wgConf = 'conf/tinkergraph-gryo.properties'
  grateful = GraphFactory.open("conf/hadoop/hadoop-grateful-gryo.properties")
  blvp = BulkLoaderVertexProgram.build().
             keepOriginalIds(false).
             writeGraph(wgConf).create(grateful)
  
negative.code: 
  [gremlin-groovy]
  ----
  hdfs.copyFromLocal('data/grateful-dead.kryo', 'data/grateful-dead.kryo')
  wgConf = 'conf/tinkergraph-gryo.properties'
  grateful = GraphFactory.open('conf/hadoop/hadoop-grateful-gryo.properties')
  blvp = BulkLoaderVertexProgram.build().
             keepOriginalIds(false).
             writeGraph(wgConf).create(grateful)
  