Initialize maxDeletedSeqno during warmup
Initialize maxDeletedSeqno during warmup

Restoring a patch that was lost during a prior rebase due to conflict
with the 2-phase warmup changeset.

The lost patch can be found below:
http://review.couchbase.org/#patch,unified,11902,8,ep.cc

Change-Id: If524dea0a00195365e179c64b02c193a82d7982a
Reviewed-on: http://review.couchbase.org/14239
Tested-by: Srinivas Vadlamani <4036f57732a648e71da3ac2c829c8239a16a4c5d@couchbase.com>
Reviewed-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>

owendCB/ep-engine,jimwwalker/ep-engine,teligent-ru/ep-engine,membase/ep-engine,membase/ep-engine,couchbase/ep-engine,daverigby/ep-engine,hisundar/ep-engine,jimwwalker/ep-engine,daverigby/ep-engine,couchbase/ep-engine,teligent-ru/ep-engine,daverigby/kv_engine,abhinavdangeti/ep-engine,hisundar/ep-engine,daverigby/kv_engine,jimwwalker/ep-engine,daverigby/ep-engine,owendCB/ep-engine,couchbase/ep-engine,hisundar/ep-engine,abhinavdangeti/ep-engine,abhinavdangeti/ep-engine,membase/ep-engine,jimwwalker/ep-engine,sriganes/ep-engine,membase/ep-engine,abhinavdangeti/ep-engine,owendCB/ep-engine,sriganes/ep-engine,owendCB/ep-engine,sriganes/ep-engine,daverigby/kv_engine,hisundar/ep-engine,abhinavdangeti/ep-engine,teligent-ru/ep-engine,daverigby/ep-engine,daverigby/kv_engine,sriganes/ep-engine,teligent-ru/ep-engine,couchbase/ep-engine