kafka-1673; potential java.lang.IllegalStateException in BufferPool.allocate(); patched by Jun Rao; reviewed by Jay Kreps
KAFKA-1668 Print an error if you try to alter a topic that doesn't exist.
kafka-1468; (followup) add back inadventently removed commit; patched by Guozhang Wang; reviewed by Jun Rao
kafka-1644; Inherit FetchResponse from RequestOrResponse; patched by Anton Karamanov; reviewed by Jun Rao
Merge remote-tracking branch 'apache/trunk' into KAFKA-1493