Improve logging in kvstore's benchmark

Change-Id: I45bc52f7e660be0e53767cc12468a6bcfe8514ac
Create the raft node before starting the listener

Change-Id: Icc582c21561150941d840e8e7d3e4cdc4a0ec6c9
Add cmd args for quiet logs and random placement

Change-Id: I37745990ddae7e37eb431647db688fb6df34f881
nit

Change-Id: I066bb628e90bfb0c2c64c274fa46fa9f43377aea
s/Do/do/g in bench

Change-Id: I41bfb06226662f836ec1bf444ec6c707323dc92a