This saga example implements a simple shell, which can,
accoriding to the SAGA philosophy, be used in a variety 
of environments.

The following commands are available:
  # pwd
  # cd      <dir>
  # ls
  # cat     <file>
  # cp      <source> <target>
  # mv      <source> <target>
  # rm      <file>
  # ln      <source> <target>
  # mkdir   <dir>
  # rmdir   <dir>
  
  # run     <exe>
  # ps
  # suspend <job>
  # resume  <job>
  # kill    <job>
  # status  <job>
  
  # set     <key> <val>
  # help
  # quit

The initial values for starting directory and default job
manager are set as environment variable.  Below are the default:

  setenv SAGA_SHELL_ROOT     file://localhost//tmp
  setenv SAGA_SHELL_CONTACT  fork://localhost/