pom.xml updates

Hi there!

I really like your improvements to Graphipedia, but I found some problems in you pom.xml files that break proper maven builds. Could you include these changes?

What's changed:

* pushed java version requirement to 1.7 (try-with-resource statements are used).
* added version number to neo4j-cypher dependency. 
* updated neo4j dependencies to 2.1.5 (this is not an issue, just revert this if you are working with an older version of neo4j)