Item12050: Eliminate obsolete spaced squab link

This removes a link format that has been deprecated since TWiki days.

[[http://some.url.com/Path Link Text]]

 - Remove the unit tests for the obsolete format
 - Add a test for the unc link with embedded spaces
 - Remove the link format from Wysiwyg TML2HTML.  (HTML2TML changes not
   needed because Wysiwyg converted from the old space delimited format
   to the supported [[http://some.url.com/Path][Link Text]] format.