Make behaviour of link field consistent to the editor

The link field can be used to store plain text and URLs as well. However the handling can be improved. If the content is a valid URL show the value as an URL (underscored, blue color). Allow same Click-functionality to open a link as is with the editor. The arrow to the right most of the edit field should be visible only, if the value is a valid URL. The same applies to the notes list. In other words make the handling smarter and make it consistent to the editor.