Clean eventDate data about daisie-checklist HOT 3 OPEN

Some intensive cleaning is needed for the dates.
On request of @stijnvanhoey and @damianooldoni , I made a branch eventDate_mapping. The file can be found here
It appears to be empty, but it's not :-)
I will try to figure out how to clean them myself, but help is always welcome (and already provided thanks to @stijnvanhoey)

from daisie-checklist.

I suspect this part of DAISIE was not well reviewed when being collated. I think we need some rules to exclude data that does not make sense. I suggest at least the following:

1. exclude any dates <0
2. exclude dates when end_year < start_year

from daisie-checklist.

Given the long discussions we've had about scope I don't suppose these records can be left out altogether. I really hate unbounded records. They tend to get interpreted as the taxon always being present, whereas frequently the reverse is true.
If you feel you have to be included them, then you could use the occurrenceStatus of doubtful, which seems appropriate in these cases.

from daisie-checklist.