./console phpci:install doesn't work out of the box

When following the current installation instructions, I got a fatal error:

```
PHP Warning:  require_once(vendor/autoload.php): failed to open stream: No such file or directory in /Users/User/git/PHPCI/bootstrap.php on line 25
PHP Stack trace:
PHP   1. {main}() /Users/User/git/PHPCI/console:0
PHP   2. require_once() /Users/User/git/PHPCI/console:4
```

Unfortunately, after running `composer install`, I still got an error:

```
PHP Warning:  require(config.php): failed to open stream: No such file or directory in /Users/User/git/PHPCI/bootstrap.php on line 26
PHP Stack trace:
PHP   1. {main}() /Users/User/git/PHPCI/console:0
PHP   2. require_once() /Users/User/git/PHPCI/console:4
```