[kicker] Never execute recent documents
Summary:
When one tried to open a recent document which happened to be
executable (a shell script, for example), it was run instead.
This was unexpected and could even be disastrous.
After this change, recent documents are always opened.
Reviewers: Plasma, hein, broulik
Reviewed By: Plasma, broulik
Subscribers: ngraham, hein, broulik, plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D10835