Changes for version 0.04
- Depends on 0.9.8+ for fixed mdb_env_copy and changed mdb_dbi_flags.
- Cache dbflags to avoid repeated function calls
- Fix custom comparators to use global $a and $b
- Add experimental LMDB_File->Flush method that commit and re-open a txn/db for continued use, proposed by Mark Zealey.
- Experimental zero-copy read mode. See LDMB_File->ReadMode
- LMDB_File - Tie to LMDB (OpenLDAP's Lightning Memory-Mapped Database)