/// <summary>
/// Creates a new domain with a given name.
/// </summary>
/// <param name="name">The name of the domain to create.</param>
/// <returns>Returns the newly created domain.</returns>
/// <exception cref="EntityAlreadyExsistsException">Thrown if the domain name is already taken.</exception>
public async Task <Domain> CreateDomain(string name)
{
if (await DomainRepository.GetDomain(name) != null)
{
throw new EntityAlreadyExsistsException("Domain", name);
}
return(await DomainRepository.CreateDomain(name));
}