Log Message:
cvsync 0.23.0 is out.

Changes:
  * Improve stability.

  * HEADS UP: Compression
    0.22.0 has a serious compression bug. If you use old versions,
    please upgrade 0.23.0 or higher. If 0.23.0 detects the remote host
    is 0.22.0, fallback to no compression mode forcibly.

  * Fix many bugs.