notify user of completed background jobs at the proper time (still doesn't work with test suite, but works with user input)
add fg built in command, make it work, and add 'status' variable to 'bgJobsL' struct
Fix job status and command recording to include null characters at the end, and make fg accept the job number instead of the job id
Add signal handlers (sigint working, sigstop not working), block and unblock sigchld to avoid race condition, implement clean exit, and more
(edit: sigstop wasn't actually fixed)