clean incorrect relu test code
relax benchmark milliseconds threshold
Merge pull request #1417 from Yangqing/dev

clean incorrect relu test code
fix relu cudnn test bug
Merge pull request #1432 from Yangqing/dev

fix relu cudnn test bug
merge
Some debugging info for when a label is not properly defined.
Fixed some CHECKs in protobuf layer.
Added the ability to shift by mean and scale by stdev to protobuf data layer labels.
Memory reclaim
More error handling for protobuf layer.
Added weights to protobuf data layer.