update operations guide for new metric names
update operations guide for new metric names

replay/metrictank,raintank/raintank-metric,raintank/metrictank,raintank/metrictank,raintank/metrictank,raintank/raintank-metric,replay/metrictank,replay/metrictank,raintank/metrictank,raintank/raintank-metric,replay/metrictank