doc improvement.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@1330 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/Main.java

@@ -21,6 +21,9 @@ import java.util.List;
 /**
  * Entry point to Hudson from command line.
  *
+ * <p>
+ * This tool runs another process and sends its result to Hudson.
+ *
  * @author Kohsuke Kawaguchi
  */
 public class Main {