Mask passwords in output configuration to avoid showing them in web.

This is just a quick & dirty fix. See #742 for a follow up issue.

Fixes #740.
Not pausing queue-based inputs for all Lifecycles != RUNNING.

Before this, queue-based inputs were paused for all lifecycle states
beside RUNNING. This would prevent any processing for lb:override states
which are independent of the message processing state.
Enable StructuredSyslogTest again.
Add fields of all SD-ELEMENTS, not just the first.

Before this only the fields of the first RFC5424 SD-ELEMENT have been
added to the fields map. This is fixed now by iterating over all
existing SD-ELEMENTS returned by the syslog parser.

Known problem:

If two different SD-ELEMENTs share the same key in the SD-PARAMS, they
overwrite each other. See code comments for details.
Update to syslog4j 0.9.49.
Start test for SyslogCodec.
Update to syslog4j 0.9.50 (because hooray for locales!)
Add BundleService#delete to REST client, refs Graylog2/graylog2-web-interface#934
avoid creating message input objects for listing their presence and attributes

this is to avoid having to do initialization work outside the constructors
input configuration and description (e.g. name, doc links etc) are independent of creating inputs and shouldn't force us to create actual input objects.
remove unused field and injected object
simplify descriptor and config classes w/respect to guice
Merge branch 'master' into input-descriptor
netty based transports erroneously shared all their channelhandlers after refactoring.

the channelpipeline factory always received the same instance from subclasses, because they were directly instantiated.
wrap each of them in a callable, for actually shared ones use Callables.returning() for convenience.

this affected only the http and tcp based transports
Mark entities with content pack they've been created from

Added attribute to Input, Output, Dashboard, Stream, and StreamRule which marks
from which content pack (by name) it was created from.

Refs Graylog2/graylog2-web-interface#937
Reduce number of empty/anonymous collections flying around
Ensure that searchHits is not null in AlertConditions

Under some conditions FieldValueAlertCondition#getSearchHits and MessageCountAlertCondition#getSearchHits
could return null which caused problems further downstream, when consumers of the respective AlertCondition
expected to always get a list of messages (though being empty if there weren't any search hits).

Refs Graylog2/graylog2-alarmcallback-slack#1
Add support for content pack marker in REST client

Refs Graylog2/graylog2-web-interface#937
Use content pack ID instead of name (which might be ambiguous)

Refs Graylog2/graylog2-web-interface#937
Add a Syslog octet counting frame decoder. (RFC6587)

See: http://tools.ietf.org/html/rfc6587#section-3.4.1

Autodetect framing type to transparently support both methods on the
same input.
refactor codec and transport guice modules to use a shared superclass with helper methods