if a script is not found, display available scripts.
Merge pull request #40 from npm/script-hints

if a script is not found, display available scripts.
better handling of paths when using run-script
Merge pull request #41 from npm/path-fixes

better handling of paths when using run-script
2.4.3
2.4.4
made args with = in middle work.
2.4.5
remove command added: will remove what generate produces