[FR]: add a section in config.json which defines a random model following the same architecture with 2 hidden layers

[xadupre]

Proposal Summary

when running the olive command with an extra parametrer (such as --test), it should use this model instead of the pretrained one

What component(s) does this request affect?

• OliveModels
• OliveSystems
• OliveEvaluator
• Metrics
• Engine
• Passes
• Other