docs: Remove `develop-theme` script, now managed elsewhere.
docs: Remove `develop-theme` script, now managed elsewhere.

Rather than developing the theme on individual docs deployments, that work
should now be done on the theme repository[0] and the example doc
deployment[1] since those repositories contain the infrastructure for testing
and deploying changes across all docs properties.  More information on
developing the theme can be found on those repository's `README.md`s.

[0] https://github.com/meteor/hexo-theme-meteor
[1] https://github.com/meteor/theme-example

apollostack/apollo-server