Cleanup (#650)

* Improve reproducibility of builds by using digest on docker images
* Inline the manifest Multi-Release entry
* Remove unused files
* Switch the groupId to org.apache.maven.daemon and use maven parent pom
* Fix distribution
* Fix ITs
* Fix native build for windows

src/main/images/mvnd-logo.svg

@@ -1,4 +1,21 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!--
+
+    Copyright 2019-2021 the original author or authors.
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+         http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+
+-->
 <svg
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:cc="http://creativecommons.org/ns#"