added generic configuration checking for inputs, instead of doing it manually in every subclass

remove checkConfiguration(Configuration) method and replaced it with setConfiguration(config) + checkConfiguration() to maintain sanity
include dropdown fields in configuration checks
Only use self-signed TLS cert/key if TLS is enabled
Remove obsolete ObjectMapper from RestApiService
honor default buffer receive size config file parameter when setting default value for interface
remove unused constant
Improve readability and completeness of PrintModelProcessor output

The previous implementation of PrintModelProcessor didn't output all registered
resources from the Jersey ResourceModel. The output is now complete, sorted and
printed through the logging subsystem instead of being dumped to stdout.
Adding maven set version backups to gitignore
Merge branch 'master' of github.com:Graylog2/graylog2-server
Fix resource filtering for graylog2-radio
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