test: tests and fixes for CID version agnostic read and write

package.json

@@ -114,7 +114,7 @@
     "ipfs-multipart": "~0.1.0",
     "ipfs-repo": "~0.26.0",
     "ipfs-unixfs": "~0.1.16",
-    "ipfs-unixfs-engine": "~0.35.2",
+    "ipfs-unixfs-engine": "~0.35.3",
     "ipld": "~0.20.1",
     "ipld-bitcoin": "~0.1.8",
     "ipld-dag-pb": "~0.15.0",

src/http/api/resources/files-regular.js

@@ -1,6 +1,6 @@
 'use strict'
 
-const mh = require('multihashes')
+const CID = require('cids')
 const multipart = require('ipfs-multipart')
 const debug = require('debug')
 const tar = require('tar-stream')
@@ -51,7 +51,7 @@ exports.parseKey = (request, reply) => {
   }
 
   try {
-    mh.fromB58String(key)
+    new CID(key) // eslint-disable-line no-new
   } catch (err) {
     log.error(err)
     return reply({