Allow patches from dependencies to be applied

Author: schlessera

composer.json

@@ -9,6 +9,7 @@
     "license": "MIT",
     "require": {
         "php": ">=5.4",
+        "cweagans/composer-patches": "^1.6",
         "wp-cli/cache-command": "^2",
         "wp-cli/checksum-command": "^2",
         "wp-cli/config-command": "^2",
@@ -53,7 +54,8 @@
     "extra": {
         "branch-alias": {
             "dev-master": "2.1.x-dev"
-        }
+        },
+        "enable-patching": true
     },
     "autoload-dev": {
         "psr-4": {