chore(package): update ipld-dag-pb to version 0.8.0 (#83)

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -33,7 +33,7 @@
     "concat-stream": "^1.5.2",
     "detect-node": "^2.0.3",
     "ipfs-block": "^0.5.0",
-    "ipld-dag-pb": "^0.1.3",
+    "ipld-dag-pb": "^0.8.0",
     "multihashes": "^0.2.2",
     "readable-stream": "2.1.5"
   },