Improve package description/readme

Author: jerowork

README.md

@@ -1,2 +1,2 @@
-# 🫚 Gember EventSourcing: Symfony Serializer
-Serializer implementation based on [symfony/serializer](https://github.com/symfony/serializer) for [gember/event-sourcing](https://github.com/GemberPHP/event-sourcing).
+# 🫚 Gember Serializer: Symfony Serializer
+Gember Serializer ([gember/event-sourcing](https://github.com/GemberPHP/event-sourcing)) implementation based on [symfony/serializer](https://github.com/symfony/serializer).

composer.json

@@ -1,9 +1,10 @@
 {
     "name": "gember/serializer-symfony",
-    "description": "Serializer implementation based on symfony/serializer for gember/event-sourcing",
+    "description": "Gember Serializer (gember/event-sourcing) implementation based on symfony/serializer",
     "license": "MIT",
     "type": "library",
     "keywords": [
+        "gember",
         "event-sourcing",
         "ddd",
         "domain-driven-design",