* Added support for killing applications to `HDInsightInstance`
  * Added support for reading HDInsight configurations from files and from a file referenced by an environment variable
  * Updated HelloHDInsight to use the environment variable to find its configuration file
minor formatting fixes
Fixing #893

Adding ResourceLaunch & ResourceRelease Handlers into the
DriverSingletons.
RunningTask.close() is now idempotent

This closes #895 by making `RunningTask.close()` idempotent. It also changes `RunningTask.close(byte[])` to throw an Exception when the Task is no longer in state `RUNNING`
Merge pull request #896 from Microsoft-CISL/weimer_895

RunningTask.close() is now idempotent
Merge pull request #897 from Microsoft-CISL/shravanmn_893

Fixing #893
Adding fixes from tr_fix
Merge remote-tracking branch 'origin/master' into shravan_groupcomm_interfaces
Baseline consistent across runs

Also fixed an issue in FailedTaskHandler