Fixing CHANGES.txt and setting release to 0.94.6-SNAPSHOT

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1446918 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7867 setPreallocSize is different with COMMENT in setupTestEnv in MiniZooKeeperCluster.java (DaeMyung Kang)

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1447105 13f79535-47bb-0310-9956-ffa450edef68