Creating 2.6.4 entries in CHANGES.txt files.

(cherry picked from commit 028894281bccd4e2f37eebff2e46409404ef64b7)

(cherry picked from commit 092c469059e32a3b45b88f24944ff31a22c4b394)

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -842,6 +842,18 @@ Release 2.7.0 - 2015-04-20
     HADOOP-11837. AuthenticationFilter should destroy SignerSecretProvider in
     Tomcat deployments. (Bowen Zhang via wheat9)
 
+Release 2.6.4 - UNRELEASED
+
+  INCOMPATIBLE CHANGES
+
+  NEW FEATURES
+
+  IMPROVEMENTS
+
+  OPTIMIZATIONS
+
+  BUG FIXES
+
 Release 2.6.3 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -1172,6 +1172,18 @@ Release 2.7.0 - 2015-04-20
       HDFS-7824. GetContentSummary API and its namenode implementation for
       Storage Type Quota/Usage. (Xiaoyu Yao via Arpit Agarwal)
 
+Release 2.6.4 - UNRELEASED
+
+  INCOMPATIBLE CHANGES
+
+  NEW FEATURES
+
+  IMPROVEMENTS
+
+  OPTIMIZATIONS
+
+  BUG FIXES
+
 Release 2.6.3 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-mapreduce-project/CHANGES.txt

@@ -300,6 +300,18 @@ Release 2.7.0 - 2015-04-20
     MAPREDUCE-6285. ClientServiceDelegate should not retry upon
     AuthenticationException. (Jonathan Eagles via ozawa)
 
+Release 2.6.4 - UNRELEASED
+
+  INCOMPATIBLE CHANGES
+
+  NEW FEATURES
+
+  IMPROVEMENTS
+
+  OPTIMIZATIONS
+
+  BUG FIXES
+
 Release 2.6.3 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-yarn-project/CHANGES.txt

@@ -913,6 +913,18 @@ Release 2.7.0 - 2015-04-20
     YARN-3466. Fix RM nodes web page to sort by node HTTP-address, #containers 
     and node-label column (Jason Lowe via wangda)
 
+Release 2.6.4 - UNRELEASED
+
+  INCOMPATIBLE CHANGES
+
+  NEW FEATURES
+
+  IMPROVEMENTS
+
+  OPTIMIZATIONS
+
+  BUG FIXES
+
 Release 2.6.3 - UNRELEASED
 
   INCOMPATIBLE CHANGES