Fix listenExceptionRemove not removing but rather consoling

Author: mbax

src/main/java/org/kitteh/irc/client/library/implementation/ClientBuilder.java

@@ -90,7 +90,7 @@ public ClientBuilder bindPort(int port) {
     @Nonnull
     @Override
     public ClientBuilder listenExceptionRemove() {
-        this.config.reset(Config.LISTENER_EXCEPTION);
+        this.config.set(Config.LISTENER_EXCEPTION, null);
         return this;
     }