updated from metalink checker trunk
added generator value carry over in conversion
migrated http link headers to slightly simpler v4 class
removing Metalinker Project as org
capability to convert moved to metalink checker
added support for generator data
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