Updated to Neo4j 2.0

I updated to Neo4j 2.0 with a few tiny changes:
* Changed version in pom.xml
* Added source/target specifications to compiler in pom.xml (to allow for annotations, because I was getting errors on my Java 1.7.0_51 (sun/oracle))
* Changed ServerBuilder to CommunityServerBuilder, since the former has been renamed in Neo4j 2.0

Then did some small cleanup:
* Fixed README path (was missing 'service' component from @Path("/service"))
* Deleted target binaries from git (probably was added in original commit by mistake)
* Changed tests to run on port 7575 to not clash with running server (saving me time)