Updates the tachyon-client version to the latest release.

The main difference between 0.7.0 and 0.7.1 on the client side is to support running Tachyon on local file system by default.

No new non-Tachyon dependencies are added, and no code changes are required since the client API has not changed.

Author: Calvin Jia <jia.calvin@gmail.com>

Closes #8235 from calvinjia/spark-9199-master.