Use SLASHSTAR instead of JAVADOC for Java

In Java JAVADOC-style comment blocks are intended for comments
interpreted by documentation building tools such as `javadoc`. Strictly
speaking, the license header block should not be interpreted by these
tools. The common approach in Java is to use the uninterpreted
SLASHSTAR-style of comments for the license header.

Recent iterations of the JDK have been getting stricter with its
parsing of Javadoc comment blocks; floating comment block not applied to
any Java element (type, method, or field) may well result in warnings in
future versions of the compiler. In JetBrain's IntelliJ Java IDE,
Javadoc-style license headers already cause a syntax warning.

While the style of comments can be configured (as mentioned in mathieucarbou#43
'License headers shouldn't be in Javadoc style') a sensible default
seems preferable.

license-maven-plugin/src/main/java/com/mycila/maven/plugin/license/document/DocumentType.java

@@ -59,8 +59,8 @@ public enum DocumentType {
     HAML("haml", HeaderType.HAML_STYLE),
     HTM("htm", HeaderType.XML_STYLE),
     HTML("html", HeaderType.XML_STYLE),
-    JAVA("java", HeaderType.JAVADOC_STYLE),
-    JAVAFX("fx", HeaderType.JAVADOC_STYLE),
+    JAVA("java", HeaderType.SLASHSTAR_STYLE),
+    JAVAFX("fx", HeaderType.SLASHSTAR_STYLE),
     JAVASCRIPT("js", HeaderType.SLASHSTAR_STYLE),
     JSP("jsp", HeaderType.DYNASCRIPT_STYLE),
     JSPX("jspx", HeaderType.XML_STYLE),

license-maven-plugin/src/test/resources/check/strict/nospace.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) ${year} http://code.google.com/p/maven-license-plugin/
  *
  * Licensed under the Apache License, Version 2.0 (the "License");

license-maven-plugin/src/test/resources/check/strict/space.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) ${year} http://code.google.com/p/maven-license-plugin/
  *
  * Licensed under the Apache License, Version 2.0 (the "License");