Add job-saving spec.

Add spec checking whether a jobseeker can save a job (after being assigned the role of a jobseeker).
Fulfill preliminary job-saving spec.

Fulfill spec confirming that jobseekers can save jobs.
Update interactions.md with feature addition.
Update interactions.md with pending feature.
Fulfill spec for saved-job reports.

Fulfill spec confirming that we can get a report which lists the jobs saved by a jobseeker.

Add SavedJob class, which delegates to other *Jobs.

Add SavedJobListReport class.

Add JobSaver#display_on.
Made method aliasing purpose explicit.

In the new utilities.rb, add HumanReadableRedirectee module. It aliases #__getobj__ to the more descriptive #redirectee.

Include HumanReadableRedirectee in all the modules that were adding that alias manually.
Add RoleDelegator before consolidating code.

Add RoleDelegator class, a child of SimpleDelegator, which will consolidate code used in the role-delegating classes and thereby make their intent more explicit.
Update to "employer" in interactions.md.

Replace "recruiter" with "employer" in interactions.md.
Update interactions.md with feature addition.
Add Reports module to lib/reports.rb.

Add Reports module, which will be used to consolidate reporting code and in hopes of later taking reporting functionality out of the data classes entirely.
Include Reports in UnpostedJob.

Refacator UnpostedJob to use Reports and Reports::reports instead of defining #display_on manually.

Make UnpostedJob#display_on just a reference to Reports#report for now, in anticipation of using "report" terminology instead of "display". This coming change will avoid confusion with the existing Object#display method.
Refactor Employer to use Reports::reports.
Replace "display" with "report" in all code.

Replace "display" with "report" in method and variables names, project-wide, to avoid confusion with Object#display. This excludes instances of "display" in the specs, which stick to the vocabularity of the original specifications.