V5 bringing RESP3, Sentinel and TypeMapping to node-redis

RESP3 Support
   - Some commands responses in RESP3 aren't stable yet and therefore return an "untyped" ReplyUnion.
 
Sentinel

TypeMapping

Correctly types Multi commands

Note: some API changes to be further documented in v4-to-v5.md

docs/command-options.md

@@ -0,0 +1,68 @@
+# Command Options
+
+> :warning: The command options API in v5 has breaking changes from the previous version. For more details, refer to the [v4-to-v5 guide](./v4-to-v5.md#command-options).
+
+Command Options are used to create "proxy clients" that change the behavior of executed commands. See the sections below for details.
+
+## Type Mapping
+
+Some [RESP types](./RESP.md) can be mapped to more than one JavaScript type. For example, "Blob String" can be mapped to `string` or `Buffer`. You can override the default type mapping using the `withTypeMapping` function:
+
+```javascript
+await client.get('key'); // `string | null`
+
+const proxyClient = client.withTypeMapping({
+  [TYPES.BLOB_STRING]: Buffer
+});
+
+await proxyClient.get('key'); // `Buffer | null`
+```
+
+See [RESP](./RESP.md) for a full list of types.
+
+## Abort Signal
+
+The client [batches commands](./FAQ.md#how-are-commands-batched) before sending them to Redis. Commands that haven't been written to the socket yet can be aborted using the [`AbortSignal`](https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal) API:
+
+```javascript
+const controller = new AbortController(),
+  client = client.withAbortSignal(controller.signal);
+
+try {
+  const promise = client.get('key');
+  controller.abort();
+  await promise;
+} catch (err) {
+  // AbortError
+}
+```
+
+## ASAP
+
+Commands that are executed in the "asap" mode are added to the beginning of the "to sent" queue.
+
+```javascript
+const asapClient = client.asap();
+await asapClient.ping();
+```
+
+## `withCommandOptions`
+
+You can set all of the above command options in a single call with the `withCommandOptions` function:
+
+```javascript
+client.withCommandOptions({
+  typeMapping: ...,
+  abortSignal: ...,
+  asap: ...
+});
+```
+
+If any of the above options are omitted, the default value will be used. For example, the following client would **not** be in ASAP mode:
+
+```javascript
+client.asap().withCommandOptions({
+  typeMapping: ...,
+  abortSignal: ...
+});
+```