Help improving the new mutt-ng documentation

Rocco Rutte started working on a new mutt-ng documentation with the focus on userfriendlyness and better structure than the old mutt documentation. Some parts have already been written, but most of the parts are still missing, so if you have some technical writing skills, and are interesting in contributing to a new and better documentation, don't hesitate to download the SGML source (LinuxDoc), add text where it is missing, and submit patches to Rocco.