Bug 1620879: Remove extraneous "/webservice" from end of plugin components

Currently, a plugin has to list its component as e.g.
"module/mobileapi/webservice". This could just be "module/mobileapi".

Since we're using the component string as part of the automated token
request system, it's better to change this now to something more sensible.

behatnotneeded: Tests to come later

Change-Id: Ia7663065b79598d92c3bf8450c5539efb6aa3e2d