RedisUtil.destroy() NullPointerException

[chrisdoc]

Environment:

atmosphere-runtime 2.4.3
atmosphere-redis 2.4.2

java -version
java version "1.8.0_77"
Java(TM) SE Runtime Environment (build 1.8.0_77-b03)
Java HotSpot(TM) 64-Bit Server VM (build 25.77-b03, mixed mode)

Exception

We are running into a NullPointerException on Line 142 when RedisUtil.destroy is called.

It tries to set the REDIS_SHARED_POOL to null config.properties().put(REDIS_SHARED_POOL, null); but atmosphere-runtime changed to a Java ConcurrentHashMap which throws NullPointerException - if the specified key or value is null. This change was introduced in Atmosphere/atmosphere@3857f68