hacked up churngenerator, if lifemean=0 and deathmean = 0, there will be no churn ----------------------------
hacked up churngenerator,
if lifemean=0 and deathmean = 0, there will be no churn
----------------------------

sit/dht,sit/dht,weidezhang/dht,sit/dht,weidezhang/dht,sit/dht,weidezhang/dht,sit/dht,weidezhang/dht,weidezhang/dht