[Constracts] Split the global CHANGELOG in dedicated CHANGELOG per contract

Author: lyrixx

CHANGELOG.md

@@ -0,0 +1,15 @@
+CHANGELOG
+=========
+
+1.1.0
+-----
+
+ * added `ServiceProviderInterface` in namespace `Service`
+
+1.0.0
+-----
+
+ * added `Service\ResetInterface` to provide a way to reset an object to its initial state
+ * added `Service\ServiceSubscriberInterface` to declare the dependencies of a class that consumes a service locator
+ * added `Service\ServiceSubscriberTrait` to implement `Service\ServiceSubscriberInterface` using methods' return types
+ * added `Service\ServiceLocatorTrait` to help implement PSR-11 service locators