Return valid WWW-Authenticate HTTP on authentication error.

Fixes #503
Stopping the rest of the services during a graceful shutdown
Revert "Stopping the rest of the services during a graceful shutdown"

Not needed. When calling System.exit() shutdown hooks are executed.

This reverts commit 16a01ba96df00296469bf054d2874b26b7419c13.
fix NPE during shutdown

this could happen when a component initiated a shutdown during our startup sequence (e.g. missing elasticsearch)
the exception was harmless, but could be misleading because it wasn't the cause of the shutdown at all

fixes #588
don't fail with NPE if input config from mongodb contains a field we don't know about

fixes #595
update drools to 6.1.0.CR1

makes it possible to load rules on the fly without creating a new session

issue #499
fix build

wrong pom dependency
use netty's Base64 codec instead of the version coming in some drools package
Adding explicit bind, optimizing imports.

Fixes #594
support AMQP vHosts. fixes #528

(cherry picked from commit cee2925d8e6b1a01c8dcf2b750f1553b2577f409)

Conflicts:
	graylog2-radio/src/main/java/org/graylog2/radio/transports/amqp/AMQPProducer.java
Fixing notifications for email alarm callback errors

Adding exception string formatter to be able to serialize full details
of exceptions.
Adding missing severity to created notifications in email alarm
callback.
Formatting exception + cause properly in notification creation.
Catching exception for individual alarm callback calls to prevent
abortion of alarm callback chain when a single one fails.

Fixes #589
Slight change to exception formatting
refactor loading drools rules

rules or rules files that fail to compile are ignored and don't cause startup failures anymore

fixes #587
issue #499
Use getAndSet() to correctly reset lastSecBytesReadTmp.
Avoiding generating expensive logging if debugging is not enabled
Merge branch 'master' of github.com:Graylog2/graylog2-server
Setting a default for the no_retention flag

Fixes #584
Merge pull request #1 from Graylog2/master

Pull updates into mah fork