update to include 2.0.0-RC3 change

/* for 2.0.0-RC3, use: console.log(node._id) */

node.id is undefined in 2.0.0-RC3
updated README to include all cases of where .id changed with 2.0.0-RC3
bumped version to 2.0.0-RC4
adding readTypedRelationshipsOfNode(node, types)
removed forgotten console.log from test
adding @wfreeman as a contributor