Allow color choices

From Anonymous on 2016/02/26 14:42:10 +0000

Green theme in new version is less distinct than yellow - orange of previous. Please allow choice in colors.

Copied from original feature request:

From Germo Görtz on 2016/06/29 13:14:38 +0000

please think about Color handicaped users which are not able to distinguish between red and green. A red line in case of error has no contrast against the green "all OK" Color.