fix for validating empty depicts year field when creating a year
fix for validating empty depicts year field when creating a year

trailbehind/Gaia-Map-Warper,trailbehind/Gaia-Map-Warper,kartta-labs/mapwarper,trailbehind/Gaia-Map-Warper,kartta-labs/mapwarper,dfurber/historyforge,DOE-NEPA/mapwarper,l34marr/mapwarper,dfurber/mapwarper,DOE-NEPA/mapwarper,kartta-labs/mapwarper,timwaters/mapwarper,kartta-labs/mapwarper,trailbehind/Gaia-Map-Warper,dfurber/historyforge,l34marr/mapwarper,dfurber/mapwarper,DistributedOpenUnifiedGovernmentNetwork/mapwarper,l34marr/mapwarper,timwaters/mapwarper,DistributedOpenUnifiedGovernmentNetwork/mapwarper,dfurber/historyforge,DOE-NEPA/mapwarper,trailbehind/Gaia-Map-Warper,DOE-NEPA/mapwarper,timwaters/mapwarper,timwaters/mapwarper,DistributedOpenUnifiedGovernmentNetwork/mapwarper,l34marr/mapwarper,DistributedOpenUnifiedGovernmentNetwork/mapwarper,dfurber/mapwarper,dfurber/historyforge,DistributedOpenUnifiedGovernmentNetwork/mapwarper,DOE-NEPA/mapwarper,dfurber/mapwarper,kartta-labs/mapwarper