- check includes
- move template functions to source file for BatchNorm and AvgPooling
- remove end-of-line spaces
- change log binded functions name convention from CamelCase to snake case

Remove 'Tensor' object include from GlobalAvgPool_Op and move setBackend member function from header to source file

This reverts commit ffc4d22e.

- type changed from 'const char*' to 'std::string'

[Add] 'Operator::backend()' member function and move Tensor dependence from header to source file when possible in operator