Update README.md

Documentation link to Github Pages moved
Merge pull request #142 from maxdemarzi/patch-1

Update README.md
Merge branch 'master' into 0.13-neo4j-2.1
Prepare release 0.13-neo4j-2.1.2
Merge pull request #143 from amorgner/0.13-neo4j-2.1

0.13-neo4j-2.1.2