zsync 0.6 released

zsync 0.6 is now available from the download page. This is mainly a maintenance release, fixing various minor bugs that people have noted over the 2 years
since the last release. I have also gone through and tidied up the source code
somewhat.

The only functional changes are:

• zsync now preserves the mtime on downloaded files (this requires an extra
  field in the .zsync, but this format change is entirely compatible with old
  clients);
• -q option replaces -s (but -s is retained temporarily as a synonym).

These make zsync align better with wget as a file download client.

The full changelog:

• fix out-of-bounds memory access when processing last block of non-compressed
  download (patch from Timothy Lee). Also fix an error handling fault for the
  same.
• fix "try a smaller blocksize" failures when zsyncmakeing for huge compressed
  files on 32bit systems
• preserve mtime on downloaded files
• fix potential crash when re/deallocating checksum hash in librcksum (patch
  from Timothy Lee)
• explain status code errors better
• better URL handling
• add -q as a substitute for -s, as -q is more conventional (re wget). -q also
  suppresses the 'no relevant local data' warning now.
• fix some warnings
• code tidy-up and better commenting of what it is doing
• tidy up autoconf use

Version 0.6 is available from the download page, as are all previous versions and the bzr repository.