Merge remote-tracking branch 'ogresCE/MAGETWO-38974-base-url-placeholder' into PR_Branch

Author: mazhalai

setup/src/Magento/Setup/Console/Command/InstallStoreConfigurationCommand.php

@@ -178,6 +178,9 @@ public function validate(InputInterface $input)
             switch ($key) {
                 case StoreConfigurationDataMapper::KEY_BASE_URL:
                     /** @var Validator $url */
+                    if (strcmp($value, '{{base_url}}') == 0) {
+                        break;
+                    }
                     $url = $this->objectManager->get('Magento\Framework\Url\Validator');
                     if (!$url->isValid($value)) {
                         $errorMsgs = $url->getMessages();