Githhub-pages site should include both Python and R package docs

[jameslamb]

Right now, we are building our Github Pages site off the docs/ folder on master. That only includes the pkgdown site for the R package.

Thanks to @csyhuang on #130 , the Python package will soon have Sphinx docs.

We should have a strategy for hosting Python and R docs together on https://uptakeopensource.github.io/uptasticsearch/

One strategy could be to write a custom index.html with links down to python-specific and R-specific folders and then to add something like this to Makefile:

site: docs_r docs_python
    mv r-pkg/docs docs/r/
    mv py-pkg/docs/built docs/py

But totally open to other suggestions! Also note that our current strategy for pkgdown has been to host all the files checked into the repo on master, but surely there must be a better way.

[jayqi]

Yes please. Also the URL to the docs site is not in the repo description as is convention.