XD-1614 Fix UTC endTime display

- The `endTime` attribute on job/step execution can be null if the job/step
execution is not yet complete by the time the test does the assertion
- Add `null` check on endTime in Job job/step execution display commands
- Fix test
XD-1620 Fix JobCommandTests

- Avoid using `JobExecution.getRows().get(0)`
  - Instead, get the matching jobExecution for the given job name and return the jobExecutionId for that row
- The same fix isn't needed for StepExecution list because they are retrieved on a given `jobExecutionId`
XD-1522: Allow only one label
XD-1365 Set ModuleDefinitions while deleteAll()

- When using AbstractDeployer.deleteAll(), the composed module definitions for the stream definition
is not set. Hence, the dependencies are not deleted from the ZK repository.
  - Fix `deleteAll()` to iteratively call delete(definitionName) which sets the ModuleDefinitions `beforeDelete`
- Remove calling `basicUndeploy()` at beforeDelete() in StreamDeployer
XD-1612 Simplify/Refactor UI controllers

- Remove unnecessary dependency injection when defining controllers
  - Inject only $scope as other dependencies are available from `xdAdmin.services`
- Create `Helper` service that returns the object representation for miscellaneous
methods such as logger, growl, timeout etc.,
XD-1612 Rename Helper service

- Rename `Helper` service -> `XDCommon` service