Add CNPC+ Api

java/noppes/npcs/api/handler/IPlayerMailData.java

@@ -0,0 +1,22 @@
+package noppes.npcs.api.handler;
+
+import noppes.npcs.api.handler.data.IPlayerMail;
+
+public interface IPlayerMailData {
+
+    boolean hasMail();
+
+    void addMail(IPlayerMail mail);
+
+    void removeMail(IPlayerMail mail);
+
+    boolean hasMail(IPlayerMail mail);
+
+    IPlayerMail[] getAllMail();
+
+    IPlayerMail[] getUnreadMail();
+
+    IPlayerMail[] getReadMail();
+
+    IPlayerMail[] getMailFrom(String sender);
+}