HUE-1857 [oozie] Allow import workflows with subworkflow identified at runtime

Save workflow without workflow in subworkflow action.
[core] fix result monitoring
HUE-1905 [core] Add security handling for yarn and mr2

Reuse security_enabled in yarn config section for both yarn and MR2 security.
Add kerberos handler for all log calls and yarn/mr2 api clients.
If a particular service is not kerberized, it should still work
since SPNEGO seems to work with insecure clusters.
HUE-218 [beeswax] Add mechanism to kill a Hive query

Works with Yarn.
Also fix query cancelling that was using the wrong id
[core] Ignore all the mo files except the ones from third parties in ext-py