This is an experimental implementation of a BundlePersistenceManager
and DataStore using a MongoDB server [1,2].

The MongoPersistenceManager is not transactional! If an error occurs while
committing changes the workspace may become inconsistent and unreadable!

Both MongoPersistenceManager and MongoDataStore support the following parameters:

- host -> defaults to "127.0.0.1"
- port -> defaults to "27017"
- dbName -> defaults to "rep" (MongoPersistenceManager) and "datastore" (MongoDataStore)
- TODO document all configuration parameters

MongoPersistenceManager also supports the following parameters:
- TODO document all configuration parameters

MongoDataStore also supports the following parameter:
- TODO document all configuration parameters

The methods related to data store garbage collection are not yet implemented.

References:

[1] http://www.mongodb.org/
[2] http://api.mongodb.org/java/current/