VBLOCKS-1808 Trimming dependencies + require => import. (twilio#175)

* VBLOCKS-1808 Removing some unwanted dependencies.
* VBLOCKS-1808 Removing deprecated dependencies as much as possible.
* VBLOCKS-1808 s/require/import/g wherever possible.

CHANGELOG.md

@@ -1,5 +1,12 @@
 2.6.1 (In Progress)
-=====================
+===================
+
+Changes
+-------
+
+- Fixed some security vulnerabilities shown by `npm audit`.
+- Removed unused dependencies.
+- Replaced deprecated dependencies.
 
 Bug Fixes
 ---------

extension/token/capabilityToken.js

@@ -2,7 +2,6 @@
 
 var _ = require('lodash');
 var jwt = require('jsonwebtoken');
-var qs = require('querystring');
 
 /**
  * @constructor

lib/twilio/call.ts

@@ -27,7 +27,7 @@ import StatsMonitor from './statsMonitor';
 import { isChrome } from './util';
 import { generateVoiceEventSid } from './uuid';
 
-const { RELEASE_VERSION } = require('./constants');
+import { RELEASE_VERSION } from './constants';
 
 // Placeholders until we convert the respective files to TypeScript.
 /**