Now mdb-exportjson output can be successfully imported into MongoDB with
mongoimport even if:
* columns have unicode names
* there are fields of binary types (e.g. OLE)
A new binary util for exporting mdb rows as json lines.
This is very useful for importing mdb data to mongo in combination with mongoimport.
The code is vastly similar to the mdb-export but there are enough dissimilarities and disagreement
about flag values that I thought a separate util is warranted.