Added Byzantium ethereumjs-blockchain GitHub version (temporary)

Author: holgerd77

package.json

@@ -19,7 +19,7 @@
   "devDependencies": {
     "babel-preset-es2015": "^6.24.0",
     "babelify": "^7.3.0",
-    "ethereumjs-blockchain": "^1.4.1",
+    "ethereumjs-blockchain": "https://github.com/ethereumjs/ethereumjs-blockchain.git#byzantium-release",
     "ethereumjs-testing": "https://github.com/ethereumjs/ethereumjs-testing",
     "ethereumjs-tx": "1.3.3",
     "level": "^1.4.0",