Ignore rule on an individual model

[nzewail]

Right now rules appear to be applied to all models by default. An ability to configure a way to ignore a specific model would be really appreciated especially as one is adopting oliver twist it can sometimes require a significant refactor to get all the models in line with the auditing rules. Being able to specific specific models to be ignored would be quite useful. This probably should be doable either in the olivertwist.yml file or in the model.yml file in the meta field specifying some kind of audit ignore