Create CODE_OF_CONDUCT.md
Create CODE_OF_CONDUCT.md

Added code of conduct from https://github.com/Bantik/contributor_covenant
doubleunion/opendiversitydata,doubleunion/opendiversitydata,ClimbsRocks/opendiversitydata,ClimbsRocks/opendiversitydata,okfse/oppnamangfaldsdata,ashleygwilliams/opendiversitydata,ashleygwilliams/opendiversitydata,okfse/oppnamangfaldsdata