1. Add mutex when operating the memory pool.
2. Support CMake 3.19 and fix some CMake bugs. Note that CUDA_ROOT variable in CMake is modified as CUDA_TOOLKIT_ROOT. You can find this update in the README.
3. Fix some bugs on Ubuntu.

1. Add mutex when operating the memory pool.
2. Support CMake 3.19 and fix some CMake bugs. Note that CUDA_ROOT variable in CMake is modified as CUDA_TOOLKIT_ROOT. You can find this update in the README.
3. Fix some bugs on Ubuntu.

1. Support Inplace way for some functions.
2. Add new flexible constructor for XList.
3. Bug fixed.

1. Offer macro to set whether use the half precision in cuda codes.
2. Update the manuals.

Support fp16 data type for more operations and fix the minor errors.  (Don't use this! It's an incomplete version)

Support fp16 data type for more operations and fix the minor errors.  (Don't use this! It's an incomplete version)

1. CPU Support for Gather function.
2. Fix the bugs in GPU Gather.
2. Minor error fixed.

1. Add boundary check for Gather 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.

1. Move the SetAscendingOrder functions from XTensor.*  to core/utilities/SetAscendingOder.*
2. Rename XElement.* files to XCall.*

1. Move the New/Initial/Del Tensor functions from XTensor.* to XElement.*
2. Move IsSameShaped functions from XTensor.* to core/shape/IsSameShaped.*
3. Move CheckData functions from XTensor.* to core/utilities/CheckData.*

2. Add MemManager class to manage the memory;
3. Use the new version XList;
4. Add a new interface to create Tensor;
5. Apply MemManager to FNNLM.