Read/Write ColorScheme to configGroup General instead of KDE

commit d59d611731e293f06ce24361aff79fb02554987f changed one of the many
places this group is used. I think it was a correct change.

This fixes all the other places.

REVIEW: 120533
Re-install test package if it already exists + wait for install to finish
Merge branch 'Plasma/5.1'
kdelibs4support--, kdelibs4support--
kdelibs4support--, convert to new connect api
Update version number for 5.1.0
ktrash is now ktrash5

BUG: 339800
fullRepresentation is null on quit
consider margins

toolbox stops dancing
Merge branch 'Plasma/5.1'
event compress panel resize when many hints change

reduces drastically size dancing
still some issues on the plasmashell part
CBUG:339207
CCBUG:337382
Merge branch 'Plasma/5.1'
don't bind the panel size

it causes the root item size to flicker when reiszing the panel

CCBUG:339207
CCBUG:337382
Merge branch 'Plasma/5.1'
Simplify subtext for empty desktops to avoid extra white space.
Merge branch 'Plasma/5.1'
fix the offset slider in vertical centered panels
fix the offset slider in vertical centered panels
fix sliders flicker on centered panels
Merge branch 'Plasma/5.1'