Port endl as \n or std::cout ... std::endl when we wrote directly on console or flush QTextStream when it's a qstring
Summary: Port endl as it's Qt:: namespaced in qt5.15
Reviewers: dfaure, dhaumann
Reviewed By: dhaumann
Subscribers: kwrite-devel, kde-frameworks-devel
Tags: Kate, Frameworks
Differential Revision: https://phabricator.kde.org/D26463