Create ORT opschema library (#7903)
* Op schema library
* Create ORT opschema library and sample app
* delete message in cmake
* Fix cmake
* Address PR feedback and add dependency
* Add cmake dependency
* Cmake fix
* Add dependency for nsync
* Add dependency for nsync
* Reorder dependencies
* Testing for dependencies on all platforms
* Resolve dependencies on GetStackTrace, floatToHalf
* Compiler strict-aliasing warning
* Merge with master
* Minor cleanup
