Adds a new content type

• command: spo contenttype add -u|--webUrl <webUrl> -n|--name <name> -i|--id <id> -d|--description [description] -g|--group [group]
• webUrl: Absolute URL of the site where the content type should be created
• name: Name of the content type
• id: ID of the content type
• description: Description of the content type
• group: Group with which the content type should be associated