docs: usage with node-redis in cluster mode

Please double-check this @gamemaker1 & @Gandalf1783

Fixes #207 (hopefully)

Author: nfriedly

readme.md

@@ -140,6 +140,7 @@ below:
 | Library                                                            | Function                                                                              |
 | ------------------------------------------------------------------ | ------------------------------------------------------------------------------------- |
 | [`node-redis`](https://github.com/redis/node-redis)                | `async (...args: string[]) => client.sendCommand(args)`                               |
+| [`node-redis`](https://github.com/redis/node-redis) (cluster)      | `async (...args) => cluster.sendCommand(undefined, false, args)`                      |
 | [`ioredis`](https://github.com/luin/ioredis)                       | `async (command: string, ...args: string[]) => client.send_command(command, ...args)` |
 | [`handy-redis`](https://github.com/mmkal/handy-redis)              | `async (...args: string[]) => client.nodeRedis.sendCommand(args)`                     |
 | [`tedis`](https://github.com/silkjs/tedis)                         | `async (...args: string[]) => client.command(...args)`                                |