Cleanup VOC data set: - removed double records, one or two pages seem to have been scanned   twice - corrected some more dates that do not fit on the Gregorian Calendar   (could not find any other calendar on which those fitted) - corrected OCR errors in numbers - corrected printing errors in numbers - added primary key constraints to the number, number_sup columns - added foreign key constraints to the voyages table
Cleanup VOC data set:
- removed double records, one or two pages seem to have been scanned
  twice
- corrected some more dates that do not fit on the Gregorian Calendar
  (could not find any other calendar on which those fitted)
- corrected OCR errors in numbers
- corrected printing errors in numbers
- added primary key constraints to the number, number_sup columns
- added foreign key constraints to the voyages table

todo:
- rename some columns (like number_sup and trip_sup_

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb