[TFB-1470] GSoC TF - TF-devstack and TF Contrail Ansible deployer

[pono]

Add a quick start guide for using Tungsten Fabric using TF-Devstack and upgrades for Contrail Ansible deployer - k8 and Openstack.

[pono]

Big thanks to nishita sikka for working on this.

I have looked at the PR (https://gerrit.tungsten.io/r/c/docs/+/37) associated with this issue and I would recommend we take a bit of a different approach. The PR essentially adds the tf-devstack code to the docs repo. This is not the approach we would like to take, so I have extracted the contents of the patch which Nishita has submitted and compared it against the current master branch for the upstream tf-devstack repo to understand the changes which were intended to be introduced.

I have isolated the proposed changes down to the following patch:

diff --git a/README.md b/README.md
old mode 100644
new mode 100755
index 7f536cf..74bde8f
--- a/README.md
+++ b/README.md
@@ -47,6 +47,8 @@ yum install -y git
{{ }} {{ git clone http://github.com/tungstenfabric/tf-devstack}} {{ cd tf-devstack}} +## Bug Fix +export K8S_VERSION=1.12.7 {{ ./startup.sh}} {{ }}

The patch essentially adds the K8S_VERSION environment variable to the docs. This change is also outlined in the following article: https://tungsten.io/getting-started-with-tungsten-fabric-using-tf-devstack/ (which Nishita added to the docs with the PR: https://gerrit.tungsten.io/r/c/docs/+/36).

I am going to revoke the PR, https://gerrit.tungsten.io/r/c/docs/+/37, as it does not conform to the documentation strategy we are trying to establish. I will leave this Jira issue open as we still have an open issue on improving the tf-devstack documentation.

I am going to approve and merge the PR, https://gerrit.tungsten.io/r/c/docs/+/36, as it introduces a valid reference to the documentation which we currently are missing in that repo. I will create another PR to then update the contents of that PR to conform to the new RTD format we are adopting, but I want Nishita's contribution to be formally merged and I will handle the clean up to make it conform to our current practices as another commit.

I hope this makes sense to everyone. Cheers...

cc: Darien Hirotsu