rdkafka_performance: -X topic... properties did not work
rdkafka_example: Added -X prop=val
examples: Added support for canonical "end","beginning","stored" to -o offset arg
Added salebab's phpkafka to list of users
Log OP_ERR right away, without need for poll, if no error_cb is set.
Added simple timers
Added consumer offset management (local file)
The application no longer needs to ignore SIGPIPE
snappy clang compilation fix
Allow producing and consuming empty messages (issue #60)