Adding Custom Vision object detection sample

[jwood803]

Adding weather recognition sample to go along with the Custom Vision ONNX tutorial

[jwood803]

@luisquintanilla, I think this is ready for review. I could have missed some stuff, so just let me know if anything needs to be updated.

[jwood803]

@luisquintanilla This should now be ready for a review

[luisquintanilla]

Additional comments:

• When using Visual Studio the output is written to the build output directory, not at the project directory level. Update paths so that we ensure regardless of whether using the CLI experience of VS, the output is written at the project directory level.
• Let's try and bump up the font size of the text and either change the color of the bounding box or bump up the thickness. Red bounding box / text on red stop sign makes it difficult to read.

[jwood803]

@luisquintanilla Updated, but let me know if any more changes are needed.

[luisquintanilla]

Thanks @jwood803. For some reason it's still not saving to the top-level directory.

[luisquintanilla]

@jwood803 check out my branch for changes that work in VS. Make sure that dotnet run gives you the same result.

https://github.com/luisquintanilla/machinelearning-samples/tree/cv-onnx/samples/csharp/end-to-end-apps/StopSignDetection_ONNX