Print out usage for individual commands
Print out usage for individual commands

- There is now an explicit 'help' command, which takes any number of
  arguments.  When given none, it duplicates the old "usage" behaviour.  When
  given one or more, it prints out only the summary of those commands.

- Documentation holes: Right now, four commands don't have doc-strings:
  list_free_nodes, project_delete, show_node, and user_delete

- Bug: The command summarizer can't deal with variable arguments, so the help
  message for 'help' is a little less descriptive than it could be.

henn/haas,henn/hil_sahil,henn/hil,SahilTikale/switchHaaS,henn/hil,apoorvemohan/haas,meng-sun/hil,kylehogan/haas,kylehogan/hil,meng-sun/hil,lokI8/haas,henn/hil_sahil,SahilTikale/haas,apoorvemohan/haas,kylehogan/hil,CCI-MOC/haas