MDL-67748 admin: Move the web services under the server administration
I suppose the original reasoning was that the web services protocols are pluggable and that plugins can provide external function. But those are not good reasons to put the whole Web services section under plugins. Web services are not a plugin type and they always felt very counter-intuitive there. From the server administrtaion perspective, web services are similar to scheduled tasks and therefore, they should live in the same section.