[New] Implemented update check setting

Setting: Plugin.Check-for-updates

Affected issues: #751

Plan/src/main/java/com/djrapitops/plan/system/settings/Settings.java

@@ -31,6 +31,7 @@ public enum Settings implements Setting {
     DISPLAY_GAPS_IN_GRAPH_DATA("Customization.Display.GapsInGraphData"),
     DATA_GEOLOCATIONS("Data.Geolocations"),
     NOTIFY_ABOUT_DEV_RELEASES("Plugin.Notify-About-DEV-Releases"),
+    CHECK_FOR_UPDATES("Plugin.Check-for-updates"),
 
     // Integer
     WEBSERVER_PORT("WebServer.Port"),

Plan/src/main/java/com/djrapitops/plan/system/update/VersionCheckSystem.java

@@ -18,6 +18,7 @@ import javax.inject.Named;
 import javax.inject.Singleton;
 import java.io.IOException;
 import java.util.List;
+import java.util.Optional;
 import java.util.stream.Collectors;
 
 /**
@@ -54,6 +55,9 @@ public class VersionCheckSystem implements SubSystem {
 
     @Override
     public void enable() {
+        if (config.isFalse(Settings.CHECK_FOR_UPDATES)) {
+            return;
+        }
         try {
             List<VersionInfo> versions = VersionInfoLoader.load();
             if (config.isFalse(Settings.NOTIFY_ABOUT_DEV_RELEASES)) {
@@ -83,7 +87,7 @@ public class VersionCheckSystem implements SubSystem {
         /* Does not need to be closed */
     }
 
-    public VersionInfo getNewVersionAvailable() {
+    public Optional<VersionInfo> getNewVersionAvailable() {
-        return newVersionAvailable;
+        return Optional.ofNullable(newVersionAvailable);
     }
 }

Plan/src/main/resources/bungeeconfig.yml

@@ -12,6 +12,7 @@ Network:
 Plugin:
   Debug: 'false'
   Locale: default
+  Check-for-updates: true
   Notify-About-DEV-Releases: false
   KeepLogsForXDays: 7
 

Plan/src/main/resources/config.yml

@@ -17,6 +17,7 @@ Plugin:
   Bungee-Override:
     StandaloneMode: false
     CopyBungeeConfig: true
+  Check-for-updates: true
   Notify-About-DEV-Releases: false
   KeepLogsForXDays: 7