RecordModel

Copyright (c) 2011 by Michael Neumann (mneumann@ntecs.de)

BUGS: 

If you don't call RecordModelLevelDB#close at the end of your program the
RecordModel class might get garbage collected before the database object is
collected (there is no order on recycling when both objects are gone).  But
when the database is closed it potentially needs to write back some data and as
such needs information from the RecordModel. If it's already recycled this is
very bad!  You can prevent that by doing:

  at_exit { db.close }