deps: remove graceful-fs

graceful-fs was added at a time when channel state was stored in
flatfiles that could become corrupted if enough concurrent saves
occurred to hit the ulimit for maxfds (EMFILE).  Saving channels this
way is no longer supported, so it shouldn't be an issue anymore.

package.json

@@ -22,7 +22,6 @@
     "cytubefilters": "github:calzoneman/cytubefilters#c67b2dab2dc5cc5ed11018819f71273d0f8a1bf5",
     "express": "^4.17.1",
     "express-minify": "^1.0.0",
-    "graceful-fs": "^4.1.2",
     "json-typecheck": "^0.1.3",
     "knex": "^0.20.3",
     "lodash": "^4.17.21",

src/channel/channel.js

@@ -1,6 +1,6 @@
 var ChannelModule = require("./module");
 var Flags = require("../flags");
-var fs = require("graceful-fs");
+var fs = require("fs");
 var path = require("path");
 var sio = require("socket.io");
 var db = require("../database");

src/logger.js

@@ -1,4 +1,4 @@
-var fs = require("graceful-fs");
+var fs = require("fs");
 var path = require("path");
 import { Logger as JsliLogger, LogLevel } from '@calzoneman/jsli';
 import jsli from '@calzoneman/jsli';