docs($compile): correct documentation for directive controller ^ notation

`^` searches the element and its parents, not exclusively the element's parents. This confuses
a lot of people :(

Closes #8622

src/ng/compile.js

@@ -191,9 +191,9 @@
  *
  * * (no prefix) - Locate the required controller on the current element. Throw an error if not found.
  * * `?` - Attempt to locate the required controller or pass `null` to the `link` fn if not found.
- * * `^` - Locate the required controller by searching the element's parents. Throw an error if not found.
- * * `?^` - Attempt to locate the required controller by searching the element's parents or pass `null` to the
- *   `link` fn if not found.
+ * * `^` - Locate the required controller by searching the element and its parents. Throw an error if not found.
+ * * `?^` - Attempt to locate the required controller by searching the element and its parents parents or pass
+ *   `null` to the `link` fn if not found.
  *
  *
  * #### `controllerAs`