Disabled PoW check

@zelig we need to discuss this

blockpool/blockpool.go

@@ -687,6 +687,8 @@ func (self *BlockPool) AddBlock(block *types.Block, peerId string) {
 		return
 	}
 
+	/*
+		@zelig needs discussing
 			// validate block for PoW
 			if !self.verifyPoW(block) {
 				plog.Warnf("AddBlock: invalid PoW on block %s from peer  <%s> (head: %s)", hex(hash), peerId, hex(sender.currentBlockHash))
@@ -698,6 +700,7 @@ func (self *BlockPool) AddBlock(block *types.Block, peerId string) {
 
 				return
 			}
+	*/
 
 	node.block = block
 	node.blockBy = peerId