Release 3.0.0.alpha.7 (the relationships edition)

 - Refactor HasN::DeclRel syntax to better match ActiveRecord
 - Add build/where functions on DeclRel collections
 - Add HasN::Rels class
 - ActiveNode#where, ActiveNode#first helpers
 - Introducing ActiveRel
Aha, sorry did not see the pull request on neo4j-core.