[Differential] [Updated] D2770: write default values in the configs

[mart (Marco Martin)]

mart added reviewers: Plasma, davidedmundson.

REPOSITORY
  rPLASMAWORKSPACE Plasma Workspace

REVISION DETAIL
  https://phabricator.kde.org/D2770

EMAIL PREFERENCES
  https://phabricator.kde.org/settings/panel/emailpreferences/

To: mart, #plasma, davidedmundson
Cc: plasma-devel, lesliezhai, ali-mohamed, jensreuterberg, abetts, sebas