Typo fix

Author: wouterj

reference/forms/types/options/html5.rst.inc

@@ -9,5 +9,5 @@ html5
 If this is set to ``true`` (the default), it'll use the HTML5 type (date, time
 or datetime) to render the field. When set to ``false``, it'll use the text type.
 
-This is usefull when you want to use a custom JavaScript datapicker, which
-often require a text type instead of a HTML5 type.
+This is useful when you want to use a custom JavaScript datapicker, which
+often requires a text type instead of a HTML5 type.