Disable debug logging in KDE 5

KDE 5 or Plasma or KF5 or whatever the hell it goes by logs WAY too much crap in the journal.

According to https://bbs.archlinux.org/viewtopic.php?id=193123 its an easy fix to disable debug logging although the kdebugdialog5 program doesn't actually do anything.

Add the lines:

QT_LOGGING_RULES="*.debug=false"
export QT_LOGGING_RULES


to /usr/bin/startkde near the top.