Adapt colour mapping in dataportals
Currently there is the possibility to adapt the color of a PresenceAbsenceTerm in a distribution map by using the according experimental feature.
There are 2 issues about it:
Currently it uses idInVocabulary, which is not necessarily a unique attribute. We should switch to uuid. Even if this is not easy to read for humans, it is exact. As this feature should be used only for exceptional cases (e.g. multiple data portals on one database) this is acceptable.
The documentation needs to be updated. It should be clearly stated that this feature should be used ONLY if the defaultColor attribute of PresenceAbsenceTerm can not be used. Also the given abbreviations for the terms should be removed as they are partly wrong now (since last model update) and should not be used anymore (see above)