Deprecate and stop using Java15Compat class.

By: md_5 <git@md-5.net>

paper-api/src/main/java/org/bukkit/util/ChatPaginator.java

@@ -2,6 +2,7 @@ package org.bukkit.util;
 
 import org.bukkit.ChatColor;
 
+import java.util.Arrays;
 import java.util.LinkedList;
 import java.util.List;
 
@@ -46,7 +47,7 @@ public class ChatPaginator {
 
         int from = (actualPageNumber - 1) * pageHeight;
         int to = from + pageHeight <= lines.length  ? from + pageHeight : lines.length;
-        String[] selectedLines = Java15Compat.Arrays_copyOfRange(lines, from, to);
+        String[] selectedLines = Arrays.copyOfRange(lines, from, to);
 
         return new ChatPage(selectedLines, actualPageNumber, totalPages);
     }

paper-api/src/main/java/org/bukkit/util/Java15Compat.java

@@ -2,6 +2,11 @@ package org.bukkit.util;
 
 import java.lang.reflect.Array;
 
+/**
+ * @deprecated Bukkit targets Java 1.6. This class will be removed in a
+ * subsequent release.
+ */
+@Deprecated
 public class Java15Compat {
     @SuppressWarnings("unchecked")
     public static <T> T[] Arrays_copyOfRange(T[] original, int start, int end) {