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

1. Fix the bugs in backward process.
2. Support the float16 class.
3. Fix bugs.
4. Clean the codes.
5. Remove the makefile.

Merge with the branch of xuchen (NOT update the float16, this needs code review) and fix the bugs in Gather function.
1. Support Reciprocal fucntion.
2. Fix the safe delete bugs in XDevice.
3. Support new API to convert the data type of tensor.
4. Support to show the memory usage of buffer memory.
5. Fix minor errors.

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

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

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.

1. fixed the bug in the Spread function.  2. add compare and OnehotAndIndex function 3. optimize the code

1. add gather function 2. add cross entropy forward computation and backward computation 3. code optimization 4. merge with xiaotong-working branch

1. add dropout function 2. add some function in tensor/core/math/unary file 3. merge with xiaotong-working branch

1. add macro to implement unary function 2. add sub and div function 3. merge code with the latest branch of xiaotong-working

1) fix the bug of unexpected breakpoints in tensor graph 2) add devID to XTensor constructor 3) avoid unneccessary data allocation in XLink

1. Bug fixed; 2. Support abs, sign, convert data type(float <->int) ;3. Merge with xu and xiao branch