This patch makes switching presentation slides using touch screen taps
more flexible. It introduces a new configuration option
'Touch navigation' with three possible values:
* 'Tap left/right side to go back/forward':
Tapping on the left(right) half of the screen
makes the presentation go to the previous(next) slide.
* 'Tap anywhere to go forward':
Tapping on the screen makes the presentation go to the
next slide, no matter where the screen is being tapped
* 'Disabled':
Screen tapping doesn't do anything.
Previously, only 'Tap anywhere...' was implemented.
This patch does not change the behavior of mouse clicks.
Differential Revision: https://phabricator.kde.org/D18118
Oliver Sander