blockmanager: Use block unlock time instead of config

lib/blockManager.js

@@ -410,7 +410,7 @@ function blockUnlocker() {
                     blockIDCache.splice(blockIDCache.indexOf(body.result.block_header.height));
                     console.log("Invalidating block " + body.result.block_header.height + " due to being an orphan block");
                 } else {
-                    if (blockHeight - row.height > global.config.payout.blocksRequired) {
+                    if (blockHeight > row.unlockHeight) {
                         blockPayments(row);
                     }
                 }