Handling of filenames in Zip's optimized. Spoken filename (no cryptic tempnames anymore). Correct filename extension, based on the mimetype.

Manual.rst: updated doc for columns  _pPdf,_zZip, _fFile. Remove doc for '_dDownload'.
Download.php: new function targetFilenameExtension(). Replace cryptic temporary filenames against file-1, ...
Link.php: reorder param array, to make TOKEN_DOWNLOAD position independet
Report.php: Implemented _pPdf,_zZip, _fFile.