Reserved comments

 AE can edit files of many programming languages. Practically any language
 that has a comment structure is fold-able. This is because the editor saves
 the fold structure of the file inside 'reserved comments' in the file.

 A 'reserved comment' is a form of comment that is reserved for use by AE
 only. The user is not permitted to enter a comment of this form into a
 file.

 Here are some examples of wise choices of reserved comment :-

      Language       Comment start and end   Reserved comment start and end

      "C"                 /*        */             /*...     */
      Assembler           ;                        ;...
      Batch               rem                      rem...
      Make                #                        #...
      Pascal              {         }              {...      }

 Note that the reserved comment starts are the comment starts plus ....
 This is an unlikely start of a comment entered by the user and so this is
 usually used to distinguish reserved comments and user supplied comments.

 It is recommended that you append ... to the comment start to give a
 reserved comment start whenever you add a language definition, to ensure
 compatiblity with everyone else. Furthermore, it is also wise not to change
 any definitions that come in the standard initialisation file AE.INI.

 An example of a reserved comment, as you might see it if you were to type
 the file or edit it with a flat editor (Pascal) :-

      {...sUpdateScreen:0:}

 To be precise, a reserved comment is recognised as a line starting with the
 reserved comment start.

 The reserved comments are set up for each language in the initialisation
 file AE.INI by language_create command.

 eg:  language_create "ada" "--..." "" ".*\\.ada" yes 2 "_."