Add sequence_number endpoint to galera server
Add sequence_number endpoint to galera server

[#106993650]

Signed-off-by: Shash Reddy <1b59e0d2ac1ccc006e81da671242cb1775d373a2@pivotal.io>

cloudfoundry-incubator/galera-healthcheck,cloudfoundry-incubator/galera-healthcheck