fixes concurrency issue due to shared instance variable for JsonGenerator #955
fixes #961 wrong content-encoding instead of content-type charset=utf-8
Check if server can be started before starting it for server tests

Make the error message a bit more explicit if there is already a neo4j instance
running on localhost:7474
Merge pull request #963 from mneedham/server-check

Check if server can be started before starting it for server tests
Merge pull request #957 from jexp/955

Eyeballed this, seems sane.
Merge pull request #962 from jexp/content-encoding

fixes #961 wrong content-encoding instead of content-type charset=utf-8
Merge remote-tracking branch 'neo4j/master' into 2.0-master-merge

Conflicts:
	community/server/src/test/java/org/neo4j/server/helpers/ServerHelper.java