1. Support int32 input data type.
2. Support GatherV2 op
3. Add transpose to ExpandDim op.

1. input_data_formats flag in yaml supports OIHW
2. MaceTensor support OIHW data format

1. Remove data_format flag for ambiguous
2. add has_data_format for distinguish models without data format.

support kaldi-onnx model convert
support validate output data from url

1. Fix random device chosen bug.
2. Add random device chosen strategy for running model.

1. Convert OpenCL binary files to code.
2. example support OpenCL byte stream with --cl_binary_to_code flag.

add onnx_optimizer tool and update onnx info in docs

1. Abstact android and arm linux to one format
2. Support cross compilation for ARM linux
3. Related issue #36