Error-out if BDBFFATAL flag is set on TokyoCabinet database

When a TokyoCabinet database is opened, the flags contained in the file
are retrieved, and checked for `BDBFFATAL`. If this flag is set, and
exception is thrown which results in the Arakoon process to quit with
return code 45.

For testing purposes, a TokyoCabinet file can be 'broken' manually by
setting bit 2 of the 34th byte in the database file.

See: ARAKOON-393
See: http://jira.incubaid.com/browse/ARAKOON-393
Merge pull request #75 from Incubaid/ARAKOON-393

Error-out if BDBFFATAL flag is set on TokyoCabinet database