Add explict this checkstyle rule and fix violations

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/BukkitBrigadierMapper.java

@@ -72,7 +72,7 @@ public final class BukkitBrigadierMapper<C> {
         /* Detect Minecraft Version Metadata */
         final String version = Bukkit.getServer().getClass().getPackage().getName();
         this.nmsVersion = version.substring(version.lastIndexOf(".") + 1);
-        final int majorMinecraftVersion = Integer.parseInt(nmsVersion.split("_")[1]);
+        final int majorMinecraftVersion = Integer.parseInt(this.nmsVersion.split("_")[1]);
 
         try {
             /* UUID nms argument is a 1.16+ feature */

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/BukkitCommandPreprocessor.java

@@ -52,9 +52,9 @@ final class BukkitCommandPreprocessor<C> implements CommandPreprocessor<C> {
      */
     @Override
     public void accept(final @NonNull CommandPreprocessingContext<C> context) {
-        context.getCommandContext().store("BukkitCommandSender", mgr.getBackwardsCommandSenderMapper().apply(
+        context.getCommandContext().store("BukkitCommandSender", this.mgr.getBackwardsCommandSenderMapper().apply(
                 context.getCommandContext().getSender()));
-        context.getCommandContext().store("CloudBukkitCapabilities", mgr.queryCapabilities());
+        context.getCommandContext().store("CloudBukkitCapabilities", this.mgr.queryCapabilities());
     }
 
 }

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/BukkitCommandSender.java

@@ -84,12 +84,12 @@ public abstract class BukkitCommandSender {
             return false;
         }
         final BukkitCommandSender that = (BukkitCommandSender) o;
-        return Objects.equal(internalSender, that.internalSender);
+        return Objects.equal(this.internalSender, that.internalSender);
     }
 
     @Override
     public final int hashCode() {
-        return Objects.hashCode(internalSender);
+        return Objects.hashCode(this.internalSender);
     }
 
     /**

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/BukkitPluginRegistrationHandler.java

@@ -64,7 +64,7 @@ public class BukkitPluginRegistrationHandler<C> implements CommandRegistrationHa
         final Field knownCommands = SimpleCommandMap.class.getDeclaredField("knownCommands");
         knownCommands.setAccessible(true);
         @SuppressWarnings("unchecked") final Map<String, org.bukkit.command.Command> bukkitCommands =
-                (Map<String, org.bukkit.command.Command>) knownCommands.get(commandMap);
+                (Map<String, org.bukkit.command.Command>) knownCommands.get(this.commandMap);
         this.bukkitCommands = bukkitCommands;
         this.bukkitCommandManager = bukkitCommandManager;
         Bukkit.getHelpMap().registerHelpTopicFactory(BukkitCommand.class, GenericCommandHelpTopic::new);

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/CloudCommodoreManager.java

@@ -60,7 +60,7 @@ class CloudCommodoreManager<C> extends BukkitPluginRegistrationHandler<C> {
                 ));
         this.brigadierManager.brigadierSenderMapper(
                 sender -> this.commandManager.getCommandSenderMapper().apply(
-                        commodore.getBukkitSender(sender)
+                        this.commodore.getBukkitSender(sender)
                 )
         );
         new BukkitBrigadierMapper<>(this.commandManager, this.brigadierManager);

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/arguments/selector/MultiplePlayerSelector.java

@@ -51,7 +51,7 @@ public class MultiplePlayerSelector extends MultipleEntitySelector {
             if (e.getType() != EntityType.PLAYER) {
                 throw new IllegalArgumentException("Non-players selected in player selector.");
             } else {
-                players.add((Player) e);
+                this.players.add((Player) e);
             }
         });
     }

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/parsers/OfflinePlayerArgument.java

@@ -219,7 +219,7 @@ public final class OfflinePlayerArgument<C> extends CommandArgument<C, OfflinePl
          * @return String value
          */
         public @NonNull String getInput() {
-            return input;
+            return this.input;
         }
 
     }

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/parsers/PlayerArgument.java

@@ -211,7 +211,7 @@ public final class PlayerArgument<C> extends CommandArgument<C, Player> {
          * @return String value
          */
         public @NonNull String getInput() {
-            return input;
+            return this.input;
         }
 
     }

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/parsers/location/LocationCoordinate.java

@@ -86,13 +86,13 @@ public final class LocationCoordinate {
             return false;
         }
         final LocationCoordinate that = (LocationCoordinate) o;
-        return Double.compare(that.coordinate, coordinate) == 0
-                && type == that.type;
+        return Double.compare(that.coordinate, this.coordinate) == 0
+                && this.type == that.type;
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(type, coordinate);
+        return Objects.hash(this.type, this.coordinate);
     }
 
     @Override

cloud-minecraft/cloud-bukkit/src/main/java/cloud/commandframework/bukkit/parsers/selector/SelectorParseException.java

@@ -69,7 +69,7 @@ public final class SelectorParseException extends ParserException {
      * @return String value
      */
     public @NonNull String getInput() {
-        return input;
+        return this.input;
     }
 
     /**