changed generated file to metalinkc.py
added support for metalink rfc format
bugfixes for metalink4 and conversions
File extension: .meta4
ran a spell check and corrected one small issue (fallback -> fall back).
improved conversion methods
added code to convert from metalink 3.0 to metalink rfc files
minor bugfix for sha512 hashes
added rev 18
metalink-17 final metalinkhttp-07 final add Alan Ford as co-author