Validator should be able to use implementation limits in JSON format.

Use the JSON format emitted by vkjson_info.

The vkjson_command queries lmits from an implementation, then dump it to JSON.
https://github.com/KhronosGroup/Vulkan-LoaderAndValidationLayers/blob/master/libs/vkjson

Start with the libs/vkjson code referenced in the issue and inspect the vkjson_info and vkjson_command entry points. Determine how implementation limits are emitted as JSON and where the validator would consume them; done means the validator accepts limits in that emitted JSON format.

Written by the indexing model from the issue text.