Expose some more settings in an Advanced dialog
Summary: Was requested by some users who needed these fields and which are already offered by NM.
Test Plan: Changed them, then changed them back.
Reviewers: Plasma, jgrulich
Reviewed By: jgrulich
Subscribers: aspotashev, broulik, ngraham, plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D22344