[FIXED HUDSON-8244] turns out Process.getErrorStream() needs to be explicitly closed even when stderr is redirected to stdout.

(Was confused by 'changelog' branch which in fact seems to be dead.
Certainly updating the file right here in master is easier.)

Regression related to HUDSON-2988 (special display of suites).

* commit '9a45f788':
  HUDSON-8252 FIXED update changelog.html appropriately
  HUDSON-8252 FIXED offline slaves wasting space in status list

There is a lot of wasted space on the Build Executor Status when
slave nodes are offline. The space can be reclaimed by simply
not displaying offline executors for offline slaves.

This is actually what I was expecting, as evident in the javadoc of XmlFile.unmarshal()

Add enforcer version to the pom so we don't try and get 1.1-SNAPSHOT (as we want reproduceable builds!)

Conflicts:
	core/src/main/java/hudson/tasks/MailSender.java