Fix wrong repldboff type which causes dropped replication in rare cases.
Only run the fast active expire cycle if master & enabled.
Merge pull request #847 from yossigo/repldboff-fix

Fix wrong repldboff type which causes dropped replication in rare cases.
Redis 2.6.17.
Deprecate Redis Sentinel in 2.6.

Everybody should use the more robust implementation shipped with 2.8.