Add more examples for better documentation.

BUG=None
TEST=unit testings for the pipeline stage, pipeline workers, generation,
steering, task, flag and hill climbing.

Change-Id: I1f8f361388d3c3171a7135d1d0ef38ee5f695829
Reviewed-on: https://gerrit-int.chromium.org/42584
Reviewed-by: Luis Lozano <llozano@chromium.org>
Commit-Queue: Yuheng Long <yuhenglong@google.com>
Tested-by: Yuheng Long <yuhenglong@google.com>
8 files changed