feat(server): switch to the bcryptjs module

The bcryptjs module is written in plain JavaScript, so it does not need
to be compiled with node-gyp (which is problematic on some platforms).

Related: #50

Author: darrachequesne

lib/index.ts

@@ -8,7 +8,7 @@ import {
   ServerEvents,
 } from "./typed-events";
 import debugModule from "debug";
-import { compare, getRounds } from "bcrypt";
+import { compare, getRounds } from "bcryptjs";
 import { isWorker } from "cluster";
 import { InMemoryStore, Store } from "./stores";
 import os = require("os");