Bump version to 1.3.2

Also bumps copyright notice to 2021.

Author: p00ya

displaymode.c

@@ -1,6 +1,6 @@
 // displaymode - a utility for changing the display resolution on Mac OS X.
 //
-// Copyright 2019, 2020 Dean Scarff.
+// Copyright 2019, 2020, 2021 Dean Scarff.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -30,7 +30,7 @@
 #include <MacTypes.h>
 
 // Name and version to display with "v" option.
-const char kProgramVersion[] = "displaymode 1.3.1";
+const char kProgramVersion[] = "displaymode 1.3.2";
 
 // States for the main invocation "option".
 //