radosgw-admin: adding radosgw-admin tests

Adding tests for syncing buckets between
RGWs. Fulfills ticket #5605.

Signed-off-by: Joe Buck <jbbuck@gmail.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
radosgw-admin: use check_status for task success

Alter the code to use the 'check_status=True'
option in rgwadmin() rather than following the
call with 'assert not err'. Should make the
tests a bit more clear and result in a more
useful error (throw the call stack rather than
just 'assert new err failed').

Signed-off-by: Joe Buck <jbbuck@gmail.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Merge pull request #44 from ceph/sentry

Add initial support for sentry
install: use get() in _get_config_value_for_remote

Fixes: #6080
Signed-off-by: Sage Weil <sage@inktank.com>
Tested-by: Tamil Muthamizhan <tamil.muthamizhan@inktank.com>
Fix upgrading edge-ish case
Merge pull request #45 from ceph/wip-6084

Fix upgrading edge-ish case
Merge pull request #47 from ceph/sentry

Make the worker obtain the correct teuthology branch
Fix SyntaxError