Set QT_QPA_PLATFORM theme to gtk2
Set QT_QPA_PLATFORM theme to gtk2

Summary:
@fix the display / customisation of KDE5 apps.
KDE5 applications don't understand anything other then gnome or kde
They expect everyone else to set QT_QPA_PLATFORMTHEME to tell them how
to theme there apps otherwise they use a fallback mode which results in
missing icons and a inability to change the appearance of applications
see https://bugzilla.suse.com/show_bug.cgi?id=920792 for more info.
There are two sensible defaults for this variable, "kde" which will
make apps appear the same as they do if they are run in kde. and gtk2
which will make kde applications follow the gtk/gnome theme, we have
decided on choosing gtk2 as it means that kde/qt apps will follow the
app and icon theme set in the enlightenment settings dialog. Some users
who wish to use Qt apps without any gnome or gtk usage may choose to
install qt5ct and overwrite this variable with qt5ct and use that to
configure there Qt5 applications.

Reviewers: raster, zmike

Subscribers: jeffhoogland, cedric

Differential Revision: https://phab.enlightenment.org/D3498

rvandegrift/e,rvandegrift/e,rvandegrift/e