Hi Nick,
it's not currently possible with Jenkins. (but even if you could the users
can still do anything including changing security permissions by running a
script in the console or uploading a plugin).
Part of what you are asking will be addressed by
https://github.com/jenkinsci/jep/pull/24
Right now I'm the only developer at the company I work for and I have
unrestricted access to Jenkins, but we need to tighten down permissions. Is
there a way to setup a new user that would be able to maintain the users
and user permissions? That user would then remove my ability to make
changes
