onnxruntime

Integrate eager mode source code into onnxruntime repo (#8584)

* integrate eager mode source codde; build with cmake and integrate the python test

* Adding the python path for importing libraries in the Eager mode

* fix clang break;check if training and python enabled

* handling the linking of torch libraries across multiple platforms

* merge and fix the naming

* add build instruction

Co-authored-by: Abhishek Jindal <abjindal@OrtTrainingDev0.af05slrtruoetgaxwwjv5nsq5e.px.internal.cloudapp.net>
Co-authored-by: ajindal1 <abjindal@microsoft.com>