[NTG-context] adding value to key

Hello, again a feature request: sometimes it's useful to add a value to key, without replacing it. Example: \setupexternalfigures[directory={\figurepathlist,another/dir}] -> \setupexternalfigures[adddirectory=another/dir] Or, if there is already some background (from an environment-file for example), and you want to add another: \setupbackgrounds[page][addbackground=Draft] Cheers, Peter -- http://pmrb.free.fr/contact/