Fixes the build after merge master --> 2.0

o Fixes cypher-plugin from pom.xml
o Changing version in pom.xmls to 2.0-SNAPSHOT
Support for getting nodes for a label.

o Added StatementContext#getNodesWithLabel (using the property store,
  just scanning it)
o Added GlobalGraphOperations#getAllNodesWithLabel
cypher: Adds support for testing label membership in WHERE