Fix for dumb bug in previous fix that extended the set of characters...

Fix for dumb bug in previous fix that extended the set of characters representing an absolute and relative URL.. thanks again to Datagrok.

lib/python/StructuredText/DocumentClass.py

@@ -951,8 +951,8 @@ class DocumentClass:
 
     ## Some constants to make the doc_href() regex easier to read.
     _DQUOTEDTEXT = r'("[ %s0-9\n\r\-\.\,\;\(\)\/\:\/\*\']+")' % letters ## double quoted text
-    _ABSOLUTE_URL=r'((http|https|ftp|mailto|file|about)[:/]+?[%s0-9_\@\.\,\?\!\/\:\;\-\#\~\=\?]+)' % letters
-    _ABS_AND_RELATIVE_URL=r'([%s0-9_\@\.\,\?\!\/\:\;\-\#\~\=\?]+)' % letters
+    _ABSOLUTE_URL=r'((http|https|ftp|mailto|file|about)[:/]+?[%s0-9_\@\.\,\?\!\/\:\;\-\#\~\=\&]+)' % letters
+    _ABS_AND_RELATIVE_URL=r'([%s0-9_\@\.\,\?\!\/\:\;\-\#\~\=\&]+)' % letters
     _SPACES = r'(\s*)'
     
     def doc_href(self, s,