README.md demo has a error

[manzhizhen]

Bug Report

This is README.md about sync demo :

StatefulRedisConnection<String, String> connection = client.connect();
RedisStringAsyncCommands<String, String> async = connection.async();
RedisFuture<String> set = async.set("key", "value")
RedisFuture<String> get = async.get("key")

async.awaitAll(set, get) == true

set.get() == "OK"
get.get() == "value"

but I find class RedisStringAsyncCommands has no "awaitAll" method，maybe this has a error.

[mp911de]

Good catch! That should had been: LettuceFutures.awaitAll