Add @Override annotations, remove unused imports,

add some copyright headers, some tab->ws


git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@21654 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/ClassicPluginStrategy.java

@@ -389,6 +389,7 @@ public class ClassicPluginStrategy implements PluginStrategy {
             this.dependencies = dependencies;
         }
 
+        @Override
         protected Class<?> findClass(String name) throws ClassNotFoundException {
             for (Dependency dep : dependencies) {
                 PluginWrapper p = pluginManager.getPlugin(dep.shortName);