v0.7.0

This is an improvement release.

It adds the support of ordered reads on the partitions of each topic. This feature is needed on applications that need total ordering on a whole topic and not only each partition. This is enabled by providing a timestamp_mapper function in the configuration. When a mapper is provided, makinage will read records of each partition with respect to increasing timestamps.
Note that total ordering is not guaranteed, but respected as much as possible: Within each partition, the records are emitted in their original order.