Add an option for via-ir for compiling solidity using the new codegen

[hrkrshnn]

From https://blog.soliditylang.org/2022/03/16/solidity-0.8.13-release-announcement/#yul-ir-pipeline-production-ready

You can enable the new pipeline using the --via-ir commandline switch or by setting settings.viaIR to true in Standard JSON input (i.e. at the same level where you would have the optimizer key).

[PaulRBerg]

Note that this can currently be done by passing a configuration file (basically, by using standard-json):

{
  "settings": {
    "viaIR": true
  }
}