ls with no parameters crashes

[Galactic Proportions]

ALSH trunk, commit "Initial commit". Python 2.6.6.

When running 'ls' with no arguments, I get the following error:

Traceback (most recent call last):
  File "./alsh", line 88, in <module>
    a.cmdloop()
  File "/usr/lib/python2.6/cmd.py", line 142, in cmdloop
    stop = self.onecmd(line)
  File "/usr/lib/python2.6/cmd.py", line 219, in onecmd
    return func(arg)
  File "./alsh", line 64, in do_ls
    l = os.listdir(path)
OSError: [Errno 2] No such file or directory: ''

[Galactic Proportions (galacpropo-deactivatedaccount-deactivatedaccount)]

Fix is commit #2.