Be consistent of type of empty URNs
Be consistent of type of empty URNs

praekelt/rapidpro,ewheeler/rapidpro,pulilab/rapidpro,praekelt/rapidpro,ewheeler/rapidpro,pulilab/rapidpro,praekelt/rapidpro,ewheeler/rapidpro,tsotetsi/textily-web,praekelt/rapidpro,tsotetsi/textily-web,ewheeler/rapidpro,tsotetsi/textily-web,pulilab/rapidpro,reyrodrigues/EU-SMS,reyrodrigues/EU-SMS,reyrodrigues/EU-SMS,pulilab/rapidpro,tsotetsi/textily-web,tsotetsi/textily-web,pulilab/rapidpro