Merge changes from topic "nn_ops_zero_size"

* changes:
  Support zero-sized input in CONCAT.
  Support zero-sized input in SLICE.
  Support zero-sized input in TRANSPOSE.
  Support zero-sized input in bbox ops.
  Support zero-sized input in quantize/dequantize ops.
  Support zero batch in activation ops.
  Support zero batch in broadcast ops.
  Support zero batch in resize_* ops.
  Support zero batch in pooling ops.
  Support zero batch in CONV_2D.
  Add check to make sure ExecutionPlan is using the selected device.
  Support zero batch in FULLY_CONNECTED.
  Support zero-sized input for ROI_ALIGN.
  Add tests for zero-sized output support.