Added shell .c files
Added header files
Revert "Added header files"

This reverts commit df92e408d6dcba8ee535da49cb8f3a8de7622c10.
Added header files
Merge branch 'job_control_shell' of https://github.com/cmh6807/xinu-arm-job-control-shell into job_control_shell
Added file descriptors for shell .c files.
Fixed ps command and added skeleton for grouping processes into jobs and having a job list
Initial function headers and method stubs
Initial function headers and method stubs
Adding source files to Makerules to make sure they are picked up by the makefile
Fixed some bugs, reset ps code back to original since fix produced an infinite loop, and added almost done jobsgroup code
Fixed printing out jobs and added an additional check to make sure the same thread is not added in a job again if it is already in a job
Got all the proper threads into a job working
Exposed variables so that other files can assess them as well
Added status printout to jobs
Patched ps, no longer infinitely loops, prints process information then exits
Updated counter as needed, added boundry check.
Added the 'jobs' command
Merge branch 'job_control_shell' of https://github.com/cmh6807/xinu-arm-job-control-shell into job_control_shell
Added help print statement.
Fixed missing parenthesis.