Updating docs link in README.

[dhermes]

@tswast Sorry I wanted to get rid of the branch in https://github.com/GoogleCloudPlatform/gcloud-python and the PR went stale.

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@daspecster We previously followed the readthedocs.org of docs at

{URI}/stable -- last release
{URI}/latest -- HEAD of source
{URI}/0.1.0
{URI}/0.2.0
{URI}/0.2.1
...

Can we restore this (outside of this PR)?

[dhermes]

@daspecster Please weigh in here

[daspecster]

We can get 0.17.0 and onward I believe, but latest and stable would have to be branches. I don't think the other languages have stable and latest but I could be wrong(I checked node and ruby). They have master and then versions.

[dhermes]

I don't think the other languages have stable and latest but I could be wrong (I checked node and ruby)

We are following a Python language / readthedocs.org convention.

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Also our old docs should be linked to (we can try to map the new docs CSS onto them, but IMO we shouldn't put the time in, we should just use the old docs)

[daspecster]

Also our old docs should be linked to (we can try to map the new docs CSS onto them, but IMO we shouldn't put the time in, we should just use the old docs)

Can you expound on this a little more?

[dhermes]

Can you expound on this a little more?

As for "linked to", see what I mean in the old docs

http://googlecloudplatform.github.io/gcloud-python/latest/
http://googlecloudplatform.github.io/gcloud-python/stable/
http://googlecloudplatform.github.io/gcloud-python/versions.html
http://googlecloudplatform.github.io/gcloud-python/0.17.0/
http://googlecloudplatform.github.io/gcloud-python/0.16.1/
etc.

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As for the CSS, I was just saying we check out the tags and run the gcloud-common generator at that point. But it's not worth it (and lots of docsets leave the old versions as-is as a rule)

[daspecster]

Ok, yeah that's why I left those in gh-pages. Where should we add the links to them? Maybe in home.html somewhere?

[dhermes]

The dropdown should just include all the versions.

Is this PR good to merge?

[daspecster]

LGTM