perf: Extract non-generic part of App::new()

Saves 5K.

src/build/app/mod.rs

@@ -116,8 +116,11 @@ impl<'help> App<'help> {
     /// # ;
     /// ```
     pub fn new<S: Into<String>>(name: S) -> Self {
-        let name = name.into();
+        /// The actual implementation of `new`, non-generic to save code size.
-
+        ///
+        /// If we don't do this rustc will unnecessarily generate multiple versions
+        /// of this code.
+        fn new_inner<'help>(name: String) -> App<'help> {
             App {
                 id: Id::from(&*name),
                 name,
@@ -139,6 +142,9 @@ impl<'help> App<'help> {
             )
         }
 
+        new_inner(name.into())
+    }
+
     /// Adds an [argument] to the list of valid possibilities.
     ///
     /// # Examples