upgrade node deps

Author: martyall

package.json

@@ -8,9 +8,9 @@
   },
   "dependencies": {
     "ethjs-provider-http": "^0.1.6",
-    "keccak": "^1.0.2",
+    "keccak": "^3.0.0",
     "rlp": "^2.0.0",
-    "secp256k1": "^3.0.1"
+    "secp256k1": "^5.0.0"
   },
   "devDependencies": {
     "purescript": "^0.15.8",