fix memory leak in sserver. 

Bitcoin mining may works well (still need more testing). Added AsicBoost support. And support AsicBoost through BTCAgent too.

stable ETH and DCR mining 

jobmaker UBTC: allow empty root state hash (00f9). 

cmake: change the package version to 2.1.0 

cmake: change package version to 2.0.0 

Merge pull request btccom#12 from btccom/develop improve format diff, O(n^2) -> O(n)