changed project version to 2.2-SNAPSHOT from 2.1.5-SNAPSHOT to reflect t...

...he Neo4j version it is using

updated Neo4j version from 2.1.5 to 2.2-SNAPSHOT
added apache commons-io dependency to account for org.neo4j.kernel.impl.util.FileUtils no longer being a public API
COMPILES BUT DOES NOT PASS TESTS (needs work to be 2.2 compatible)