#2 Cross Contamination Feature

[Christian Thöns]

I created this ticket to write down some things regarding cross contamination, that were discussed in the EFSA telephone conferences:

1. At some stations cross contamination is impossible since the food is not touched (e.g. at some traders). This could be implemented by a "crossContaminationPossible" flag for stations.
2. At some stations cross contamination could only happen for certain deliveries (e.g. some stations open strawberries and process them, but they do not touch berry mixes). This could be implemented by a "crossContaminationPossible" flag for deliveries.