Merge develop

NOTICE

 Apache RocketMQ
-Copyright 2016-2017 The Apache Software Foundation
+Copyright 2016-2018 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
\ No newline at end of file

pom.xml

@@ -262,6 +262,7 @@
                         <exclude>src/main/resources/META-INF/service/*</exclude>
                         <exclude>*/target/**</exclude>
                         <exclude>*/*.iml</exclude>
+                        <exclude>docs/**</exclude>
                     </excludes>
                 </configuration>
             </plugin>

remoting/src/main/java/org/apache/rocketmq/remoting/netty/NettyRemotingAbstract.java

@@ -446,7 +446,8 @@ public abstract class NettyRemotingAbstract {
             final SemaphoreReleaseOnlyOnce once = new SemaphoreReleaseOnlyOnce(this.semaphoreAsync);
             long costTime = System.currentTimeMillis() - beginStartTime;
             if (timeoutMillis < costTime) {
-                throw new RemotingTooMuchRequestException("invokeAsyncImpl call timeout");
+                once.release();
+                throw new RemotingTimeoutException("invokeAsyncImpl call timeout");
             }
 
             final ResponseFuture responseFuture = new ResponseFuture(channel, opaque, timeoutMillis - costTime, invokeCallback, once);