[WIP] Prettify the Accounts KCM and expand KAccounts integration library

Summary:
This is a WIP which aims to expand and beautify the KAccounts integration
code and visuals. A great deal of work to be done, but didn't want it just
sitting on my machine (because that's just to scary)

Just the commit message pile for now, also cleanup of that later:

* Rename the job code files to somethingjob (part of larger refactor)
* Also rename the job code itself
* Add a model to expose the list of accounts
* Add a model for exposing the services for a single account
* Fix uipluginsmanager compilation
* Add i18n and jobs to the kaccounts library
* Expose the jobs and models to qml, and simplify plugin to only exposing
* Add self to kcm authors list
* Switch to using our jobs and models in Accounts (and prettify)
* Expand the services page (should probably be AccountDetails now...)
* A tiny bit of work on the add account page (much more to do)

Differential Revision: https://phabricator.kde.org/D27681