* Moved OneHot to v0

* Introduced OneHot:v1

* Added shape calculation for OneHot:v1

* Added element types checking

* Added output shape tests

* Added tests to checking if inputs are scalars

* Updated OneHot:v1 doc

* Implemented OneHot:v1 downgrade pass

* Using OneHot:v1 in onnx_importer

* Implemented OneHot:v0 upgrade

* Fixed OneHot onnx_importer

* Refactored normalize_axis

* Added OneHot:v1 serialized

* Code review remarks introduced

* Added doc to normalize_axis