Merge pull request #519 from eric-wu/release-1

Adjust throughputs according to the most recent monitoring
Remove logging the metric as CloudWatch is showing the correct numbers
Better metric names and other code optimization
PLFM-1975 Turn on CloudWatch metrics for the controllers
Remove the controller CloudWatch switch in testing as it is turned on by default in prod
Merge pull request #522 from eric-wu/quickfix

Light refactoring for dynamo workers
Merge branch 'release-1' into quickfix
Merge pull request #523 from eric-wu/quickfix

Merge down from release-1