Reword some text, a couple clean ups, add a separator

Summary: Re-word some menu items per T8552#140370

Test Plan:
before:

after

Reviewers: ngraham, Frameworks, VDG, GB_2

Reviewed By: ngraham, VDG, GB_2

Subscribers: kde-frameworks-devel

Tags: Frameworks, VDG

Differential Revision: https://phabricator.kde.org/D20827