Implemented a basic form of the cd command.
The command can go back to the home directory if no arguments are
    passed to it.
Have yet to test going back to home directory via the ~ and multiple
     destinations.
Going into other directories does not work.
The prompt now displays the current directory.
Completed implementation of the cd command.
The program will jump to a valid location if it is the only one
    given.
The program can handle cd used with connectors.
The program will yield undefined behavior if used with piping or
    redirection.