Fix one typo on Tempest manual

[Toru Tanami]

Fix one typo on Tempest Coding Guide.

docstings => docstrings

http://docs.openstack.org/developer/tempest/HACKING.html#tempest-specific-commandments

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/212822

[Xicheng Chang (xichengchang)]

Tanami: I submitted a CL and did not realize that you already assigned it to yourself. Would you like me to abandon that CL? My apologies.

[Toru Tanami (tanami)]

xichengchang: I would like to fix this bug in myself.
Can I assign this bug to me again?

[Xicheng Chang (xichengchang)]

tanami: I have added you to my CL's reviewers list. Please -1 that change and add another CL that closes this bug. hudson will automatically re-assign this bug to you.

[Toru Tanami (tanami)]

Sorry.
It seems like this bug's review is in progress.
So Please proceed as it is.

Please assign this bug to you again.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/212822
Committed: https://git.openstack.org/cgit/openstack/tempest/commit/?id=6fb98ec0844fdb20a73ea534ee94961467a02a8e
Submitter: Jenkins
Branch: master

commit 6fb98ec0844fdb20a73ea534ee94961467a02a8e
Author: Xicheng Chang <email address hidden>
Date: Thu Aug 13 14:02:52 2015 -0700

    Fix typo in Tempest Coding Guide.

    "doctstrings" was mis-spelled as "docstings" in
    tempest/HACKING.html

    Change-Id: I0ae2b84af718cc032cd031612a898895a2b3c21d
    Closes-bug: #1484356

[Xicheng Chang (xichengchang)]

tanami: I am so sorry they ignored my "-1" and approved it. Is there anything I can do? Would you like me to find a bug for you?

[Toru Tanami (tanami)]

I'm okay.
I already found another bug. Thanks.