Training: Fix error with tensors being unexpectedly doubles.

training/test.lua

@@ -39,6 +39,7 @@ function test()
       donkeys:addjob(
          function()
             local inputs, labels = testLoader:sampleTriplet(opt.batchSize)
+            inputs = inputs:float()
             return sendTensor(inputs)
          end,
          testBatch

training/train.lua

@@ -50,6 +50,8 @@ function train()
          function()
             local inputs, numPerClass = trainLoader:samplePeople(opt.peoplePerBatch,
                                                                  opt.imagesPerPerson)
+            inputs = inputs:float()
+            numPerClass = numPerClass:float()
             return sendTensor(inputs), sendTensor(numPerClass)
          end,
          -- the end callback (runs in the main thread)