chore(package): update multihashes to version 0.3.0 (#40)

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -40,7 +40,7 @@
   "dependencies": {
     "async": "^2.0.1",
     "libp2p-crypto": "^0.7.0",
-    "multihashes": "^0.2.2"
+    "multihashes": "^0.3.0"
   },
   "repository": {
     "type": "git",