function ExternalServiceViewModel()
{
    this.el = '#external-service-options';
    this.data = {
        service_type: ''
    };
    this.computed = {
        isDropbox: function()
        {
            // This logic must be mirrored in App\ExternalService
            return this.service_type === 'dropbox';
        },
        isFacebook: function()
        {
            // This logic must be mirrored in App\ExternalService
            return this.service_type === 'facebook';
        },
        isGoogle: function()
        {
            // This logic must be mirrored in App\ExternalService
            return this.service_type === 'google';
        },
        isTwitter: function()
        {
            // This logic must be mirrored in App\ExternalService
            return this.service_type === 'twitter';
        }
    }
}