Download bigtable-hbase-dataflow-tools JAR file with all dependencies

This project contains artifacts that provide utility functions for Cloud Bigtable client readers and writers in Google Cloud Dataflow. Dataflow includes a different version of the cloud bigtable client, resulting in a need to have a separation of concerns and an abstraction. More importantly, there is a need for shading and renaming of packages so that Dataflow nad bigtable-hbase-dataflow's two sets of shading (needed for a variety of reasons) don't clash with each other. This submodule does package renaming which is needed for bigtable-hbase-dataflow and alleviates some issues related to developing that module.