[MRESOURCES-293] Make resources param not read-only (#54)

Actually, test-resources were already not read-only, change
applies only to resources mojo.

---

https://issues.apache.org/jira/browse/MRESOURCES-293

Author: cstamas

src/main/java/org/apache/maven/plugins/resources/ResourcesMojo.java

@@ -80,7 +80,7 @@ public class ResourcesMojo
     /**
      * The list of resources we want to transfer.
      */
-    @Parameter( defaultValue = "${project.resources}", required = true, readonly = true )
+    @Parameter( defaultValue = "${project.resources}", required = true )
     private List<Resource> resources;
 
     /**

src/main/java/org/apache/maven/plugins/resources/TestResourcesMojo.java

@@ -49,7 +49,7 @@ public class TestResourcesMojo
     /**
      * The list of resources we want to transfer.
      */
-    @Parameter( defaultValue = "${project.testResources}", required = true, readonly = false )
+    @Parameter( defaultValue = "${project.testResources}", required = true )
     private List<Resource> resources;
 
     /**