Update example:

- load vendor/autoload.php
dynamically generate command completions
strict requirement
Basic zsh completion generator
skip hidden commands
document todo
implements getArgumentsInfo for the command arguments
Add ArgumentInfo class and its test file.
Add desc field to ArgumentInfo
Add docblock
Translate ReflectionParameter into ArgumentInfo
Rename method to hasCommands
Add ArgumentInfo tester
Add arginfo command test
update README
describe arginfo
provide better help printing
refactoring help command class
Rename demo.php to demo
Fix zsh completion generator