Bump version 2.8.0 (#151)

Author: mfl28

build.gradle

@@ -33,7 +33,7 @@ plugins {
 }
 
 group 'com.github.mfl28'
-version '2.7.0'
+version '2.8.0'
 
 repositories {
     mavenCentral()

src/main/java/com/github/mfl28/boundingboxeditor/controller/Controller.java

@@ -83,7 +83,7 @@ public class Controller {
     private static final String PROGRAM_NAME = "Bounding Box Editor";
     private static final String PROGRAM_NAME_EXTENSION_SEPARATOR = " - ";
     private static final String GITHUB_WIKI_URL = "https://github.com/mfl28/BoundingBoxEditor/wiki";
-    private static final String PROGRAM_VERSION = "2.7.0";
+    private static final String PROGRAM_VERSION = "2.8.0";
     private static final String PROGRAM_LICENSE = "GPL-3.0";
     private static final String PROGRAM_IDENTIFIER = PROGRAM_NAME + " " + PROGRAM_VERSION;
     private static final String OPEN_FOLDER_ERROR_DIALOG_TITLE = "Image Folder Loading Error";