JS module command-lines now supported quoted arguments (w/white-space)

Example:
Command-line: ?showargs   " a b c "d "e f"
argc = 3
argv[0] = ' a b c '
argv[1] = 'd'
argv[2] = 'e f'   

This resolves a long-standing TODO comment.

Also, fixed a problem where multiple spaces between the module name and the first argument would result in argv[0] being set to an empty string.