add /status endpoint to nodejs server + test
synced code with most recent changes
updated Spark job UI to display the collected metrics in blocks
Merge pull request #645 from caskdata/feature/nodejs-healthcheck

add /status endpoint to nodejs server + test
fixed comments
fixed comments
Merge pull request #662 from cybervisiontech/CDAP-652-spark-job-metrics-blocks

CDAP-652: updated Spark job UI to display the collected metrics in blocks
fixed comments
Merge pull request #660 from cybervisiontech/CDAP-713/HelloWorld-example-archetype

CDAP-713: Update HelloWorld example archetype
Revert "CDAP-652: updated Spark job UI to display the collected metrics in blocks"
Merge pull request #664 from caskdata/revert-662-CDAP-652-spark-job-metrics-blocks

Revert "CDAP-652: updated Spark job UI to display the collected metrics ...
CYB #91: Unit test for Spark Page Rank example