Summary:
Caffe2: add a DB that's wrapped around a BlobsQueue as an adapter for data from non-DB interface.
This is useful for bridging the gap between DB interface data processing ops (TensorProtosDBInput, ImageInputOp etc.) and data that's coming from arbitrary Python or the pretty intricate Hive reader.
Reviewed By: akyrola
Differential Revision: D5554560
fbshipit-source-id: 01bb0056410f9ade205367d5fefc721f91f5b629