D19132: Update libs/widgets to c++11

[Carl Schwan]

ognarb edited the summary of this revision.

REPOSITORY
  R8 Calligra

REVISION DETAIL
  https://phabricator.kde.org/D19132

To: ognarb, #calligra:_3.0
Cc: Calligra-Devel-list, dcaliste, cochise, vandenoever