More updates for CLI help

Author: mikera

convex-cli/src/main/java/convex/cli/ACommand.java

@@ -22,7 +22,7 @@ public abstract class ACommand implements Runnable {
 	public abstract Main cli();
 
 	public void showUsage() {
-		CommandLine cl=new CommandLine(this);
+		CommandLine cl=new CommandLine(this.getClass());
 		showUsage(cl);
 	}
 

convex-cli/src/main/java/convex/cli/Help.java

@@ -10,7 +10,7 @@
 
 @Command(
 		name="help",
-		description="Show usage help",
+		description="Show usage help and exit.",
 		helpCommand = true)
 public class Help extends ACommand implements IHelpCommandInitializable2  {
 

convex-cli/src/main/java/convex/cli/account/Account.java

@@ -22,7 +22,6 @@
 		AccountInformation.class,
 		CommandLine.HelpCommand.class
 	},
-	mixinStandardHelpOptions=false,
 	description="Manage Convex accounts.")
 public class Account extends ATopCommand  {