Clean the codes.

1. Supporting efficient propagate and gradient accumulation for backward functions.
2. Update the setData functions.
3. Clean the codes.

1. Add boundary check for Gather function.
2. Minor error fixed.

Fix the bugs in CUDA 10.

Minor error fixed.

Fix the dimension bugs in Stack functions.

Minor error fixed.

Minor error fixed.

1. Fix the bugs for MatrixMul functions which may cause nan in some cases. (IMPORTANT)
2. Fix the minor errors.

1. Offer global setting for enableGrad.
2. Update XList.
3. Minor error fixed.

Minor error fixed.

Fix the GPU bug in Clip function.

1. Support X_INT dataType for Clip and ScaleAndShift function.
2. Minor error fixed.

1. Support X_INT dataType for Sum function.
2. Minor error fixed.

1. Support to copy parts of source tensor to parts of target tensor.
2. New unit test for CopyIndex function.

Add a new parameter isSorted in TopK function to sort the items in the top-k pool.

1. Backward bugs fixed.
2. Fix the minor errors.

1. Support scalar tensor for Multiply and Div operation;
2. Fix backward bugs in Multiply and Div function;
3. Minor bugs fixed.

Fix backward bugs in MulAndShift function.

ReduceSum and ReduceMax bug fixed.

Support scalar tensor for MulAndShift operation.

New unit test for Sub function.

Minor bugs fixed.

Minor bugs fixed.

Support scalar tensor for Sub operation.

1. Support scalar tensor for Sum operation;
2. Bounds check;
3. GetSumDimIndex function bug fixed;
4. New unit test for Sum function;
2. Minor bugs fixed.

Boundary detection (order >= 0) bug fixed.

1. Make link for ReduceSumAll function.
2. Fix the memory leak issue.

Use tensor as the bottom implementation and support plain scalar.
Note: DO NOT support the backward for ReduceSumAll function.