Add recipe for loophp/psr17 package.

loophp/psr17/1.0/config/packages/loophp_psr17.yaml

@@ -0,0 +1,9 @@
+services:
+    # Register loophp/psr17/Psr17 class and autowire/autoconfigure it.
+    loophp.psr17.psr17:
+        class: loophp\psr17\Psr17
+        autowire: true
+        autoconfigure: true
+
+    # Alias the service to the Psr17 interface.
+    loophp\psr17\Psr17Interface: '@loophp.psr17.psr17'

loophp/psr17/1.0/manifest.json

@@ -0,0 +1,5 @@
+{
+    "copy-from-recipe": {
+        "config/": "%CONFIG_DIR%/"
+    }
+}