Update CONTRIBUTORS.txt

:)
Conflicts:
	CONTRIBUTORS.txt
Merge branch 'master' of github.com:celery/celery
Add /etc/init.d/celerybeat status

Design copied from extra/generic-init.d/celeryd
Tested on Ubuntu 12.04 LTS
Multi: Now outputs to stdout instead of stderr for non-errors
generic init: celeryd status now gets pidfiles using multi expand (Issue #1942)
Bump celerybeat init script version and cosmetics for #1942