def add_site (site)
      return nil if @sites.map{|s| s[:name]}.include? site
      raise JSS::InvalidDataError, "No site in the JSS named #{site}" unless JSS::Site.all_names(api: @api).include? site
      @sites << {:name => site}
      @need_to_update = true
    end
def add_site (site)
      return nil if @sites.map{|s| s[:name]}.include? site
      raise JSS::InvalidDataError, "No site in the JSS named #{site}" unless JSS::Site.all_names(api: @api).include? site
      @sites << {:name => site}
      @need_to_update = true
    end
Add this user to a site

 @param site[String] the name of the site

 @return [void]