Fixed dd_user and dd_group reference in datadog::integrations::nginx.
Added 'log_level' class variable to manipulate agent's log levels.
Merge branch 'loglevel' into leo/packaging

Conflicts:
	manifests/init.pp
	manifests/integrations/nginx.pp
	templates/datadog.conf.erb
Ensure datadog-agent-base is not here for 5.0