Things has been simplified over time and my old guide about Git Commands has been improved a bit.
At least in the context of removing remote branches. Now, it's as easy as passing
--delete parameter along with pushing changes to the server.
git push origin --delete <remote_branch_name>
Response will look like following:
To github.com:phofman/xyz_project.git - [deleted] <remote_branch_name>
What is even more beautiful in this syntax is that it also works for remote tags!