0.4.0:
  - fixed bug which could cause backup file to become corrupt in event of
    machine that crashed during the write
  - a bit reorganization which makes NFSStore slower but more robust.
  - added test directory.  see test/README
0.3.0:
  - fixed bug where the unache used flock/fcntl even when
    NFSStore#dont_use_nfslock == true.
  - also saw first hand how crappy the nfs lock client can be on some sun
    sytems, locking process up most of the time...  probably users will want to
    use NFSStore.dont_use_nfslock on these systems...
  - general clean-up of code
0.2.0:
  - fixed open mode in transaction (must always be 'rb+' not 'rb')
  - added default timeout to #snapshot
0.1.0:
  - general clean up and some commenting
  - mods to #transaction and #snapshot to make them more robust in face of
    unexpected errors
  - if using nfslocking a file is made containing the node, pid, ppid, and time
    the lock was obtained so it's easy to clean up if some sick process on some
    node holds the lock
0.0.0:
  - initial version