D15279: Store all annotation color attributes as ARGB string

[Tobias Deiminger]

tobiasdeiminger added a dependent revision: D15204: Add typewriter annotation 
tool.

REPOSITORY
  R223 Okular

REVISION DETAIL
  https://phabricator.kde.org/D15279

To: tobiasdeiminger
Cc: okular-devel, ngraham, aacid