merge rel-0.4.0 into master (#959)

* Accomodate missing optional 'axes' when 'steps' is present in Slice op (#946)

* Accomodate missing optional axes when steps is present in Slice implementation

* PR feedback

* Update package links (#937)

* Update package links

* Minor fix

* Update README.md

* Minor edit

* Update onnx commit (#949)

* Update onnx commit

* disable failing tests which don't have to be fixed for this release

* dummy change to fix file permission

* fix file permission