Implement option to toggle page navigation wraps around for pager plasmoid

Summary:
BUG: 361672

This patch implement an option to disable navigation wraps around for the pager plasmoid, which potentially cause inconveniences for user who switch desktop using mouse wheel or touchpad scroll.

The patch is implemented since "Desktop navigation wraps around" option in "System Settings -> Desktop Behavior -> Virtual Desktops -> Switching" only affects keyboard shortcut mapping.

Reviewers: Plasma, VDG, davidedmundson

Reviewed By: Plasma, davidedmundson

Subscribers: hein, zzag, ngraham, abetts, davidedmundson, broulik, plasma-devel

Tags: Plasma

Differential Revision: https://phabricator.kde.org/D14988