Fix various minor issues

src/math/vec.rs

@@ -118,6 +118,12 @@ impl FGVec2 {
         (to - self).length()
     }
 
+    #[inline]
+    #[must_use]
+    pub fn distance_squared(self, to: Self) -> FGWide {
+        (to - self).length_squared()
+    }
+
     #[inline]
     pub fn normalize(&self) -> Option<Self> {
         let x = I32F32::from_num(self.x);