* added end-to-end nuget package test
* reset the changes in OnnxRuntime.CSharp.proj
* revert the testdata directory path
* revert inference tests proj file
* added script for running end-to-end tests
* fix in the runtest.bat
* added error checking in runtest
* fixed paths in the test project
* added runtest.sh
* fix protoc path
* updated executable attributes for the runtest scripts
* added some log to debug protoc failures
* removed the protoc and duplicate test code, reuse unit-test code for end-to-end test
* copy always
* fix working dir paths in runtest.sh
* added a build.py flag to download test data without running the c++ tests
* added a script for running the test under docker
* added script for docker run of the test