Issue #3087626 by greg.1.anderson, Mixologic, jibran, Mile23, alexpott, xjm:...

Issue #3087626 by greg.1.anderson, Mixologic, jibran, Mile23, alexpott, xjm: Convert drupal/core-recommended & c. into a subtree split

composer.json

+{
+    "name": "drupal/core-recommended",
+    "type": "metapackage",
+    "description": "Locked core dependencies; require this project INSTEAD OF drupal/core.",
+    "license": "GPL-2.0-or-later",
+    "conflict": {
+        "webflo/drupal-core-strict": "*"
+    },
+    "require": {
+        "drupal/core": "self.version",
+        "asm89/stack-cors": "1.2.0",
+        "composer/installers": "v1.7.0",
+        "composer/semver": "1.5.0",
+        "doctrine/annotations": "v1.4.0",
+        "doctrine/cache": "v1.6.2",
+        "doctrine/collections": "v1.4.0",
+        "doctrine/common": "v2.7.3",
+        "doctrine/inflector": "v1.2.0",
+        "doctrine/lexer": "1.0.2",
+        "easyrdf/easyrdf": "0.9.1",
+        "egulias/email-validator": "2.1.11",
+        "guzzlehttp/guzzle": "6.3.3",
+        "guzzlehttp/promises": "v1.3.1",
+        "guzzlehttp/psr7": "1.6.1",
+        "masterminds/html5": "2.7.0",
+        "pear/archive_tar": "1.4.8",
+        "pear/console_getopt": "v1.4.2",
+        "pear/pear-core-minimal": "v1.10.9",
+        "pear/pear_exception": "v1.0.0",
+        "psr/container": "1.0.0",
+        "psr/http-message": "1.0.1",
+        "psr/log": "1.1.0",
+        "ralouphie/getallheaders": "3.0.3",
+        "stack/builder": "v1.0.5",
+        "symfony-cmf/routing": "2.1.0",
+        "symfony/class-loader": "v3.4.32",
+        "symfony/console": "4.4.x-dev",
+        "symfony/debug": "4.4.x-dev",
+        "symfony/dependency-injection": "4.4.x-dev",
+        "symfony/error-handler": "dev-master",
+        "symfony/error-renderer": "4.4.x-dev",
+        "symfony/event-dispatcher": "4.4.x-dev",
+        "symfony/event-dispatcher-contracts": "v1.1.7",
+        "symfony/http-foundation": "4.4.x-dev",
+        "symfony/http-kernel": "4.4.x-dev",
+        "symfony/mime": "v4.3.5",
+        "symfony/polyfill-ctype": "v1.12.0",
+        "symfony/polyfill-iconv": "v1.12.0",
+        "symfony/polyfill-intl-idn": "v1.12.0",
+        "symfony/polyfill-mbstring": "v1.12.0",
+        "symfony/polyfill-php72": "v1.12.0",
+        "symfony/polyfill-php73": "v1.12.0",
+        "symfony/process": "4.4.x-dev",
+        "symfony/psr-http-message-bridge": "v1.2.0",
+        "symfony/routing": "4.4.x-dev",
+        "symfony/serializer": "4.4.x-dev",
+        "symfony/service-contracts": "v1.1.7",
+        "symfony/translation": "4.4.x-dev",
+        "symfony/translation-contracts": "v1.1.7",
+        "symfony/validator": "4.4.x-dev",
+        "symfony/yaml": "4.4.x-dev",
+        "twig/twig": "v1.42.3",
+        "typo3/phar-stream-wrapper": "v3.1.3",
+        "zendframework/zend-diactoros": "1.8.7",
+        "zendframework/zend-escaper": "2.6.1",
+        "zendframework/zend-feed": "2.12.0",
+        "zendframework/zend-stdlib": "3.2.1"
+    }
+}