* Cherry picked fix on python Schema API

* Merge Rel 1.1.0 branch into master (#657)

* Increase Version number for release 1.1.0

* Increase version number to 1.1.1

(cherry picked from commit ecac1c162485b3d6072eff73dbbc79fd5376c8ff)

* Fix some checks not ideal to onnx-ml (#781)

* Fix some checks not ideal to onnx-ml

1. Need to consider cases where no default ONNX operator set exists
2. Cannot assume that value_info's are all tensors (CoreML's neural
network classifiers contain ZipMap, the they may produce Maps)

* Address comments and improve some more error messages

* Make SSA not abbreviated

* Address a comment

* a fix

(cherry picked from commit e3da0f9babe700fde5b70c998b3104a91cacbca5)

* Cherry picked updated testcases

* Cherry pick updates on testcases (1)

* Remove incorrect cases (#791)

* Update the remainig cases (#794)

* Fix incorrect conflict merge

* Remove unpassed testcases

* Bump up version number

* Kezhan/update ml op spec (#799)

* update normalizer.

* update ml op spec.

* update traditional ops.

* update ml op doc

(cherry picked from commit bf00ae6118cc50d045494679f3ec53ec2d2cd552)