“Moves” instead of “copies” in <Option<T> as From<T>>::from doc.

This implementation has no `Copy` or `Clone` bound, so its operation is
guaranteed to be a move. The call site might copy, but the function
itself cannot.

Also linkify `Some` while we're touching the line anyway.

Author: kpreid

library/core/src/option.rs

@@ -1701,7 +1701,7 @@ impl<'a, T> IntoIterator for &'a mut Option<T> {
 
 #[stable(since = "1.12.0", feature = "option_from")]
 impl<T> From<T> for Option<T> {
-    /// Copies `val` into a new `Some`.
+    /// Moves `val` into a new [`Some`].
     ///
     /// # Examples
     ///