Changes on feature/bazel-update branch.

Build scripts have been mostly updated, but still need to:

• remove --incompatible_merge_genfiles_directory=false from bazelrc
• remove --incompatible_new_actions_api=false from bazelrc
• remove --incompatible_no_support_tools_in_action_inputs=false from bazelrc
• update CI docker image to use latest version of Bazel