Revised asakusa-on-emr documents (#420).
Fixed document - invalid code examples (#420).
Revised directio/using-hive document (#420).
Revised ThunderGate documents using Gradle (#420).
Bumped up target EMR version (#420).
Fixed document typo (#420).
Fixed Release date (#420).
Merge remote-tracking branch 'private/issue/420-M32' into 0.7-develop