Preliminary job type check spec.

Add preliminary spec which checks whether jobseekers can apply to ATS-type jobs without a resume.
Fulfill ATS job submission spec.

Fulfill spec that checks whether jobseekers can apply to ATS-type jobs without a resume.

Add Submission and NoResume classes.
Add spec for ATS job applications with resumes.

Add a spec confirming that jobseekers cannot use a resume when applying to to ATS-type jobs. This is not in the original spec but was clarified later.
Fulfill ATS application check for resumes.

Fulfill spec confirming that jobseekers cannot include resumes when applying to ATS-type jobs.

Add Resume class. Add #exists? to Resume and NoResume.

Add Jobseeker#draft_resume.