Renamed external scheme display name and added urn schemes to reserved words for contact field keys
Renamed external scheme display name and added urn schemes to reserved words for contact field keys

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