ceph_objectstore_tool: Add task for testing of tool of the same name

Based on ceph/src/test/ceph_objectstore_tool.py but only does
replicated pool testing and doesn't test argument validation.

Signed-off-by: David Zafman <david.zafman@inktank.com>
ceph_manager: Implement export/import when thrasher kills an osd

Use list-pgs to avoid races by seeing actual pgs present

Signed-off-by: David Zafman <david.zafman@inktank.com>
ceph_manager: Add test code to use export/import to move a pg

Check for more than 1 osd down and randomize on chance_move_pg (100%)
For now only export from older down osd to newly down osd to avoid missing map

Signed-off-by: David Zafman <david.zafman@inktank.com>