Konsole should use new process when some Qt/KDE options are given

One typical option is "--display", because two konsole windows
belonging to the same process are destined to be shown in the same
display, which defeats the purpose of the "--display" option

CCBUG: 297224

BUG: 179010
BUG: 297801
FIXED-IN: 4.9.0
REVIEW: 104653