make framework.Parameter public

Replace lod with recursive_sequence_lengths in book examples

add timeline_cn

fix analysis compile bug

optimize doc for host_memory_profiling_cn

fix tensorrt compiler bug

* small AverageOptimizer enhance.

* clean

* clean

fix trainer nccl2 env

* Add fill_zeros_array op. This op is used for zero-filling an LoDTensorArray.

* merge fill_zeros_array_op with fill_zeros_like_op

* add unit_test for fill_zeros_like for array

fix adam op for selected rows

Add unit test for testing distributed training with mnist

add option to compile inference demo

* bnorm+relu fuse for mkldnn

* separate fuse_relu function

* bug fix

* proper while range in inference_transpiler

* description fix

* review fix

* review fix

* unit test for fwd batch norm+relu MKLDNN fuse

small clean

* optimize bipartite_match_op in large scale input

* Speed depthwise transposed conv2d.

* Set zero outside functor

Add Python Reader Op (CPP side)

Add design doc of Python data feeding

create about_us.rst