radio inputs should not be exclusive

this allows to pull data from multiple broker setups

fixes #681
InputService.find() throws exception when record is not found.

This prevents an NPE when find() is called for non-existing input
ids.

Fixes #684
Source input of message might be null when input was deleted before.
FQCN not needed here.
Replacing wildcard imports with explicit ones.
Merge pull request #686 from Graylog2/issue684

InputService.find() throws exception when record is not found.
Add flag to pwgen example to only output one password.
Add organization, mailingLists, and other metadata to POM
Add license-maven-plugin to take care of license headers
Update license headers in source files
Merge pull request #678 from Graylog2/maven-license-plugin

Add License Maven Plugin
Replace org.graylog2:gelfj with org.graylog2:gelfclient
Use gelfclient 1.0.0 release version
Upgrade to Jersey 2.11 and HK2 2.3.0-b10
Get rid of reflection-based monkey-patching of HK2

Instead of trying to override hard-coded defaults in the Injections class,
now the standard Java SPI (ServiceLoader) is being used. The required
Injector instance is created and held by the new GuiceInjectorHolder class
and used by Graylog2ServiceLocatorGenerator.
Merge pull request #675 from Graylog2/jersey-2.11

Upgrade to Jersey 2.11 and HK2 2.3.0-b10
Added from and to field to query responses
Revert "Upgrade to Jersey 2.11 and HK2 2.3.0-b10"
Merge pull request #688 from Graylog2/revert-675-jersey-2.11

Revert "Upgrade to Jersey 2.11 and HK2 2.3.0-b10"
Returning Optional from cache as CacheLoader does not like null values.

Fixes #684