Introduce bashate

This commit introduces bashate[0] which is a code style checker for bash
scripts. We already have some bash scripts in Tempest repo. So, it might
be good to check the style automatically.

Some scripts under the tools directory are also fixed due to the bashate
violation.

Change-Id: I07820f10387552f93a9d8891b58a8c7fcdb83046
5 files changed