Adding custom fields onto the POST /v1/jobs endpoint.

Currently there is not a way to add custom fields through the API because it is not listed in the model schema. It would be useful to add the custom fields into the model schema for the jobs endpoint. 

This would benefit our customers who work with 3rd parties as they seek for custom solutions as it would be a way to automate some portions of creating a job as it will reduce the amount of CSRs needed to book these jobs. This will allow the company to be more efficient an optimize their resources more efficiently in the areas that they could be spending more time working on. 

The recommended solution is to add the custom field model onto the model schema and allow 3rd party engineers to build a more refined solution with the jobs endpoint so that CSRs are not needing to go back into the job and adding the custom fields.