docs(yaml): make sure the doc-tests don't fail before "missing file"

Removing an unused import is the only visible change.

src/app/mod.rs

@@ -130,11 +130,15 @@ impl<'a, 'b> App<'a, 'b> {
     /// of an [`App`] struct.
     ///
     /// ```ignore
+    /// # #[macro_use]
+    /// # extern crate clap;
     /// # use clap::App;
+    /// # fn main() {
     /// let yml = load_yaml!("app.yml");
     /// let app = App::from_yaml(yml);
     ///
     /// // continued logic goes here, such as `app.get_matches()` etc.
+    /// # }
     /// ```
     /// [`App`]: ./struct.App.html
     /// [`examples/17_yaml.rs`]: https://github.com/kbknapp/clap-rs/blob/master/examples/17_yaml.rs

src/args/arg.rs

@@ -135,9 +135,13 @@ impl<'a, 'b> Arg<'a, 'b> {
     /// # Examples
     ///
     /// ```ignore
+    /// # #[macro_use]
+    /// # extern crate clap;
     /// # use clap::Arg;
+    /// # fn main() {
     /// let yml = load_yaml!("arg.yml");
     /// let arg = Arg::from_yaml(yml);
+    /// # }
     /// ```
     /// [`Arg`]: ./struct.Arg.html
     #[cfg(feature = "yaml")]

src/args/group.rs

@@ -119,9 +119,13 @@ impl<'a> ArgGroup<'a> {
     /// # Examples
     ///
     /// ```ignore
+    /// # #[macro_use]
+    /// # extern crate clap;
     /// # use clap::ArgGroup;
+    /// # fn main() {
     /// let yml = load_yaml!("group.yml");
     /// let ag = ArgGroup::from_yaml(yml);
+    /// # }
     /// ```
     #[cfg(feature = "yaml")]
     pub fn from_yaml(y: &'a Yaml) -> ArgGroup<'a> {

src/args/subcommand.rs

@@ -57,9 +57,13 @@ impl<'a> SubCommand<'a> {
     /// # Examples
     ///
     /// ```ignore
-    /// # use clap::{App, Arg, SubCommand};
+    /// # #[macro_use]
+    /// # extern crate clap;
+    /// # use clap::Subcommand;
+    /// # fn main() {
     /// let sc_yaml = load_yaml!("test_subcommand.yml");
     /// let sc = SubCommand::from_yaml(sc_yaml);
+    /// # }
     /// ```
     #[cfg(feature = "yaml")]
     pub fn from_yaml(yaml: &Yaml) -> App {

src/macros.rs

@@ -13,11 +13,15 @@
 /// of an `App` struct.
 ///
 /// ```ignore
+/// # #[macro_use]
+/// # extern crate clap;
 /// # use clap::App;
+/// # fn main() {
 /// let yml = load_yaml!("app.yml");
 /// let app = App::from_yaml(yml);
 ///
 /// // continued logic goes here, such as `app.get_matches()` etc.
+/// # }
 /// ```
 #[cfg(feature = "yaml")]
 #[macro_export]