docs: add 4.0.0-rc upgrade guide (#822)

CHANGES.md

@@ -1,7 +1,7 @@
 twilio-node changelog
 =====================
 
-[2022-11-16] Version 4.0.0-rc.0
+[2022-11-30] Version 4.0.0-rc.0
 ---------------------------
 - Release Candidate prep
 

UPGRADE.md

@@ -1,6 +1,52 @@
-Upgrade Guide
+# Upgrade Guide
 
-After 3.0.0 all MINOR and MAJOR version bumps will have upgrade notes posted here.
+_All `MAJOR` version bumps will have upgrade notes posted here._
+
+[2022-11-16] 3.x.x to 4.x.x
+-----------------------------
+
+* Supported Node.js versions updated
+  * Upgrade to Node.js >= 14
+  * Dropped support for Node.js < 14 ([#791](https://github.com/twilio/twilio-node/pull/791))
+  * Added support for Node.js 18 ([#794](https://github.com/twilio/twilio-node/pull/794))
+* Lazy loading enabled by default ([#752](https://github.com/twilio/twilio-node/pull/752))
+  * Required Twilio modules now lazy load by default
+  * See the [README](README.md) for how to disable lazy loading
+* JWT token building deprecations
+  * `ConversationsGrant` has been deprecated in favor of `VoiceGrant` ([#783](https://github.com/twilio/twilio-node/pull/783))
+  * `IpMessagingGrant` has been removed ([#784](https://github.com/twilio/twilio-node/pull/784))
+* TwiML function deprecations ([#788](https://github.com/twilio/twilio-node/pull/788))
+  * `Refer.referSip()` replaced by `Refer.sip()`
+  * `ssmlBreak()` replaced by `break_()`
+  * `ssmlEmphasis()` replaced by `emphasis()`
+  * `ssmlLang()` replaced by `lang()`
+  * `ssmlP()` replaced by `p()`
+  * `ssmlPhoneme()` replaced by `phoneme()`
+  * `ssmlProsody()` replaced by `prosody()`
+  * `ssmlS()` replaced by `s()`
+  * `ssmlSayAs()` replaced by `sayAs()`
+  * `ssmlSub()` replaced by `sub()`
+  * `ssmlW()` replaced by `w()`
+    * Old:
+    ```js
+    const response = new VoiceResponse();
+    const say = response.say("Hello");
+    say.ssmlEmphasis("you");
+    ```
+    * New:
+    ```js
+    const response = new VoiceResponse();
+    const say = response.say("Hello");
+    say.emphasis("you");
+    ```
+* TaskRouter Workers Statistics operations updated ([#820](https://github.com/twilio/twilio-node/pull/820))
+  * Cumulative and Real-Time Workers Statistics no longer accept a WorkerSid
+  * `GET /v1/Workspaces/{WorkspaceSid}/Workers/CumulativeStatistics`
+    * Old: `client.taskrouter.v1.workspaces('WS...').workers('WK...).cumulativeStatistics()`
+    * New: `client.taskrouter.v1.workspaces('WS...').workers.cumulativeStatistics()`
+  * `GET /v1/Workspaces/{WorkspaceSid}/Workers/RealTimeStatistics`
+    * Old: `client.taskrouter.v1.workspaces('WS...').workers('WK...).realTimeStatistics()`
+    * New: `client.taskrouter.v1.workspaces('WS...').workers.realTimeStatistics()`
 
 [2017-05-22] 3.1.x to 3.2.x
 ---------------------------