HBASE-8430 Cell decoder/scanner/etc. should not hide exceptions

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.95@1478654 13f79535-47bb-0310-9956-ffa450edef68
HBASE-8466  Netty messages in the logs

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.95@1478666 13f79535-47bb-0310-9956-ffa450edef68