/// Defines the developers’ preferred display mode for the website.
/// ## Example
/// ```rust
/// # extern crate webmanifest;
/// # extern crate failure;
/// # use webmanifest::{Manifest, DisplayMode};
/// # fn main() -> Result<(), failure::Error> {
/// let name = "My Cool Application";
/// let manifest = Manifest::builder(name)
/// .display_mode(DisplayMode::Standalone)
/// .build()?;
/// # Ok(())}
/// ```