D27640: templates: Convert license statements to SPDX headers

[Friedrich W. H. Kossebau]

kossebau marked an inline comment as done.

REPOSITORY
  R242 Plasma Framework (Library)

REVISION DETAIL
  https://phabricator.kde.org/D27640

To: kossebau, #plasma, cordlandwehr
Cc: kde-frameworks-devel, LeGast00n, cblack, GB_2, michaelh, ngraham, bruns