Add go-up/down/next/previous-skip
Summary:
These are meant to be used when moving by the normal amount (go-up/down/next/previous) is too slow, but skipping all the way to the end of something is too far (go-top/bottom/first/last).
Turn window-keep-* into symlinks to go-up/down-skip
Requested by @laysrodrigues for Atelier
Test Plan:
Reviewers: VDG, Atelier, ngraham
Reviewed By: VDG, ngraham
Subscribers: abetts, ngraham, laysrodrigues, kde-frameworks-devel
Tags: Frameworks
Differential Revision: https://phabricator.kde.org/D20435