Merge pull request #80 from subvertallchris/master

cypher queries handle nil property values correctly
single ExecutionEngine instance in embedded DB
Merge pull request #83 from subvertallchris/master

single ExecutionEngine instance in embedded DB
Probably not done, but all the specs are passing!  Removed QueryBuilder and replaced with Query class.  Query can now take a session and users can now call session.query in order to get a query for that session.  Some improvements to the Query API as I went through the session shared specs
Remove debugging line
Merge branch 'master' into query

Conflicts:
	lib/neo4j-core/query_builder.rb
	spec/neo4j-core/unit/query_builder_spec.rb
Fixing the embedded side.  Getting closer, but need to sleep...
Merge branch 'query' of github.com:andreasronge/neo4j-core into query

Conflicts:
	lib/neo4j-embedded/embedded_session.rb
	lib/neo4j-server/cypher_response.rb