docs($compile): remove obsolete sentence

Fixes angular#15109

Closes angular#15119

Author: thorn0

src/ng/compile.js

@@ -267,14 +267,14 @@
  * and other directives used in the directive's template will also be excluded from execution.
  *
  * #### `scope`
- * The scope property can be `true`, an object or a falsy value:
+ * The scope property can be `false`, `true`, or an object:
  *
- * * **falsy:** No scope will be created for the directive. The directive will use its parent's scope.
+ * * **`false` (default):** No scope will be created for the directive. The directive will use its
+ * parent's scope.
  *
  * * **`true`:** A new child scope that prototypically inherits from its parent will be created for
  * the directive's element. If multiple directives on the same element request a new scope,
- * only one new scope is created. The new scope rule does not apply for the root of the template
- * since the root of the template always gets a new scope.
+ * only one new scope is created.
  *
  * * **`{...}` (an object hash):** A new "isolate" scope is created for the directive's element. The
  * 'isolate' scope differs from normal scope in that it does not prototypically inherit from its parent