reply-header-string patch

   This patch makes it possible to specify what header is to be inserted in
   a message when replying to a message. In standard Pine, the header is
   fixed to the format 'On Dd Mmmm Yyyy, Xxxxx wrote:' This patch will let
   you specify your own header, with the new setup option
   reply-header-string. These tokens are identified and will be substituted
   for real data when the header is inserted:
   _YEAR_ (4-digit) , _MONTH_, _DAY_ (both 2-digit), DATE_ (long format),
   _FROM_ (original sender's name).

  Written by: Peter Karlsson