Metalinks Code

segmented downloads and checksum checking (MD5 and SHA1), possible libraries:

- phex - This just seems to parse out the magnet links
- jdownloader - too integrated with too many other libraries
- http://code.google.com/p/metalink/source/browse/#svn/trunk/src/org/heresylabs/metalink
- https://hc.apache.org/httpcomponents-client-ga/

Nice to have: chunk checksums, meta4 support, resume a download between sessions