Add Missing dep concat-stream

Author: bcomnes

package.json

@@ -20,6 +20,7 @@
   },
   "homepage": "https://github.com/bcomnes/random-access-http#readme",
   "dependencies": {
+    "concat-stream": "^1.5.1",
     "inherits": "^2.0.1",
     "mkdirp": "^0.5.1",
     "pump": "^1.0.1",