Implements Inspect.conf command for getting worker configuration
celery inspect stats contains worker pid
pep8/cosmetics
Implements new task_retry signal.  Closes #1169
Fixes deprecation message
Merge branch '3.0' of github.com:celery/celery into 3.0
Implements new task_retry signal.  Closes #1169
Add myself to contributors
Fixes chord bug when processing IGNORED tasks

Should not run on_chord_part_return, task_after_return,
nor send_postrun when task was IGNORED or RETRIED
Can only check Pool.did_start_ok at startup.  Closes #1118
subtask.id is now an alias to subtask['options']['task_id']
result.join_native now respects propagate argument
Add link to internals guide from contributor doc
Defines what happens when a chord task fails.  Closes #1172
improves docstring
Typo in /etc/init.d/celery usage help
Retry sending task-sent event if connection failed.
Disable execv by default
Configure multiprocessing with loglevel ERROR by default (if MP_LOG envvar not set)
events dumper (-d) now retries on connection failure