Fix X-Y-Z and NPE while running TTL on backup V2.
(#827) Removing functionality of creating incremental manifest file in backup V1 as it is not used.
(#827) Bug fix: When meta file do not exist for TTL in backup v2 we should not be throwing NPE.
(#827) Bug fix: Fix X-Y-Z issue using gossip status information instead of gossip state. Note that gossip status is (JOINING/LEAVING/NORMAL) while gossip state is (UP/DOWN). Gossip state is calculated individually by all the Cassandra instances using gossip status.