fixes glitch where an empty tag shows up

with dummy change in readme to be able to make a commit

After discussions with the Stackdriver team, they did not think this was
needed.

Grafana high availability (ha) test setup

stackdriver: broadcasting through $scope doesnt work anymore since query_filter_ctrl is now a sibling directive to query_aggregation_ctrl, so broadcasting is now done using $rootScope

Adding AWS Isolated Regions

Plugin list to react

Compile TS on precommit hook

- was not covered by TS lint
- TS errors are only noticed in broken builds
- added grunt task to run `tsc --noEmit`