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/WebAppMain.java

@@ -185,6 +185,7 @@ public final class WebAppMain implements ServletContextListener {
             context.setAttribute(APP,new HudsonIsLoading());
 
             new Thread("hudson initialization thread") {
+                @Override
                 public void run() {
                     try {
                         context.setAttribute(APP,new Hudson(home,context));