error: InvalidArgumentException...

Click on menu in Admin - settings/contenttypes.

```error: InvalidArgumentException```

````The "/home/bolt/websiteX/app" directory does not exist. -
/vendor/symfony/finder/Symfony/Component/Finder/Finder.php:667
/vendor/bolt/bolt/app/classes/lib.php:1515````

If Bolt is running under vendor folder as part of other Composer based project leads to error.
Both ```app``` and ```theme``` paths corrected although just ```app``` causing error. 
(I think theme path should be also aligned but I'm nit sure...)