Support for e2e key backups

package.json

@@ -56,6 +56,7 @@
     "babel-runtime": "^6.26.0",
     "bluebird": "^3.5.0",
     "browser-request": "^0.3.3",
+    "bs58": "^4.0.1",
     "content-type": "^1.0.2",
     "loglevel": "1.6.1",
     "qs": "^6.5.2",

spec/unit/crypto.spec.js

@@ -69,6 +69,7 @@ describe("Crypto", function() {
 
             mockBaseApis = {
                 sendToDevice: expect.createSpy(),
+                getKeyBackupVersion: expect.createSpy(),
             };
             mockRoomList = {};
 
@@ -111,9 +112,7 @@ describe("Crypto", function() {
                 getSender: expect.createSpy().andReturn('@bob:home.server'),
             });
 
-            console.log("waiting");
             await prom;
-            console.log("done");
         });
     });
 });