modularized metalink download/parse process, removed -f, added convert options
added piece count for v3 chunk checksums
fixed sort order for metalink v4 urls
fixes added for signatures and more tag conversions
changed merged binary to metalinkc
updated for new metalink library with v4 support
added support for converting between v3 and v4
added number formatting for file size
minor updates
metalink-18, metalinkhttp-08 final