0.05
    - Add new concurrency test

0.04
    - Die if a file already exists but there is no prev entry (insert instead
      of update).

0.03
    - Allow passing 'nfs', 'global_lock' and 'auto_commit' flags to
      Directory::Transactional
    - Update dependency on Directory::Transactional to 0.03

0.02
    - Delegate txn_do methods
    - Update dependency on Directory::Transactional to 0.02

0.02_02
    - Update dep on KiokuDB

0.02_01
    - Use Directory::Transactional to provide transaction support

0.01 (JSPON 0.06)
    - Rename to KiokuDB::Backend::Files
    - add 'create' attribute
    - switch to Serialize::Delegate
    - add trie support

0.05
    - Depend on a more recent IO (binmode method is missing in older ones)
    - Refactor JSON handling and move to KiokuDB core

0.04
    - update test suite to not use KiokuDB::Resolver
