update dependencies and rename module

renaming the module from github.com/trivago/gollum to just gollum
fixes issues with accidentally importint the previous gollum tag
instead of using the current module.

add new formatter docs

Respect cgroup limits (#256)

* use cgroup limit for maxproc if no cpu count is set

* update changelog and dependencies

* add note that -n 0 respects cgroup limits

update spooling test config

update consumer.file docs

Update changelog

 s/Issue/Error/ in error messages (#227)

* Grammar fix and s/Issue/Error/ in error messages

fix processtsv unittests

Merge pull request #215 from trivago/SyslogMetadata

Syslog metadata support

fix metadatacopy to actually copy the payload and not reference it