Add new section on trait bounds.

exercises/04_traits/14_outro/tests/integration.rs

@@ -0,0 +1,16 @@
+use outro_03::SaturatingU16;
+
+#[test]
+fn test_saturating_u16() {
+    let a: SaturatingU16 = (&10u8).into();
+    let b: SaturatingU16 = 5u8.into();
+    let c: SaturatingU16 = u16::MAX.into();
+    let d: SaturatingU16 = (&1u16).into();
+
+    assert_eq!(a + b, SaturatingU16::from(15u16));
+    assert_eq!(a + c, SaturatingU16::from(u16::MAX));
+    assert_eq!(a + d, SaturatingU16::from(11u16));
+    assert_eq!(a + a, 20u16);
+    assert_eq!(a + 5u16, 15u16);
+    assert_eq!(a + &u16::MAX, SaturatingU16::from(u16::MAX));
+}