So, since I want to work with neo4j through bulbs, it seems that I have no other option but to use Groovy Gremlin.
Installation of groovy on Eclipse: through marketplace. Quite easy.
First attempt to use: install gremlin from Tinkerpop and access it from Groovy programming shell in eclipse. After about an hour of furious googling, it seems that a couple of libraries need to be included in the groovy shell to launch the gremlin from within groovy:
gremlin$ groovysh -cp $GREMLIN_HOME/lib/gremlin-groovy-2.3.0.jar:$GREMLIN_HOME/lib/gremlin-java-2.3.0.jar:$GREMLIN_HOME/lib/pipes-2.3.0.jar:$GREMLIN_HOME/lib/common-1.7.jar:$GREMLIN_HOME/lib/groovy-1.8.9.jar
To do the same thing from Eclipse, Project>Properties>JavaBuild Path>Add External Jars
and then add:
$GREMLIN_HOME/lib/gremlin-groovy-2.3.0.jar
$GREMLIN_HOME/lib/gremlin-java-2.3.0.jar
$GREMLIN_HOME/lib/pipes-2.3.0.jar
$GREMLIN_HOME/lib/common-1.7.jar
$GREMLIN_HOME/lib/groovy-1.8.9.jar