If you get this error:
Fatal error: Class 'IntlDateFormatter' not found in magento2/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php on line 107
that means you need to install Intl php extension.
In order to do it you should go to your php.ini file and uncomment this line:
... ;extension=php_intl.dll ...
... extension=php_intl.dll ...
and restart your nginx.
If after that you get an error below:
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/Cellar/php55/5.5.30/lib/php/extensions/no-debug-non-zts-.../php_intl.dll'
that means you don’t have the library php-intl.dll and you need to install it.
There are different ways to do it, but in brew you can run command:
brew install php55-intl
it would install the library and create required configuration file: