Improve documentation and changelog ref

Author: blacelle

lib/src/cleanthat/java/com/diffplug/spotless/glue/java/JavaCleanthatRefactorerFunc.java

@@ -30,6 +30,10 @@
 import eu.solven.cleanthat.engine.java.refactorer.JavaRefactorerProperties;
 import eu.solven.cleanthat.formatter.LineEnding;
 
+/**
+ * The glue for CleanThat: it is build over the version in build.gradle, but at runtime it will be executed over
+ * the version loaded in JarState, which is by default defined in com.diffplug.spotless.java.CleanthatJavaStep#JVM_SUPPORT
+ */
 public class JavaCleanthatRefactorerFunc implements FormatterFunc {
 	private static final Logger LOGGER = LoggerFactory.getLogger(JavaCleanthatRefactorerFunc.class);
 

lib/src/main/java/com/diffplug/spotless/java/CleanthatJavaStep.java

@@ -39,6 +39,7 @@ public final class CleanthatJavaStep {
 	private static final String NAME = "cleanthat";
 	private static final String MAVEN_COORDINATE = "io.github.solven-eu.cleanthat:java";
 
+	// CleanThat changelog is available at https://github.com/solven-eu/cleanthat/blob/master/CHANGES.MD
 	private static final Jvm.Support<String> JVM_SUPPORT = Jvm.<String> support(NAME).add(11, "2.1");
 
 	// prevent direct instantiation

plugin-maven/README.md

@@ -278,7 +278,7 @@ These mechanisms already exist for the Gradle plugin.
 
 ### Cleanthat
 
-[homepage](https://github.com/solven-eu/cleanthat). CleanThat enables automatic refactoring of Java code
+[homepage](https://github.com/solven-eu/cleanthat). CleanThat enables automatic refactoring of Java code. [ChangeLog](https://github.com/solven-eu/cleanthat/blob/master/CHANGES.MD)
 
 ```xml
 <cleanthat>