POST /job endpoint

[rusher2004]

Create the POST /job endpoint for the creation of jobs.

When creating a job, the resource will be created by a user, and is owned by a company (might be renamed to organization). The user attempting to create the job should have the create_job permission from the company.

As of now, the required values for a job object are title and description, both text types. Likely more will be needed. Other specific details (pay rate, employment type, etc.) will be on the job_posting resource.