add returnee calendar manager to claim rewards

Author: anjeshshrestha

api/src/main/java/eu/darkbot/api/managers/ReturneeAPI.java

@@ -0,0 +1,52 @@
+package eu.darkbot.api.managers;
+
+import eu.darkbot.api.API;
+
+import java.util.List;
+
+/**
+ * Provide access to Returnee data
+ */
+public interface ReturneeAPI extends API.Singleton {
+
+    /**
+     * @return if one time login reward is claimable
+     */
+    boolean isLoginClaimable();
+
+    /**
+     * @return {@code List} of all Rewards for one time login claimable
+     */
+    List<? extends LoginRewardList> getLoginRewardList();
+
+    /**
+     * Provide access to one time Reward data in Retunee window containing loot id and amount of the item
+     */
+    interface LoginRewardList {
+        String getLootId();
+
+        double getAmount();
+    }
+
+    /**
+     * @return if daily calendar reward is claimable
+     */
+    boolean isCalendarClaimable();
+
+    /**
+     * @return {@code List} of all Daily calendar rewards
+     */
+    List<? extends CalendarRewardList> getCalendarRewardList();
+
+    /**
+     * Provide access to daily  calendar reward data in Retunee window containing
+     *      loot id and amount of the item, and if claimed
+     */
+    interface CalendarRewardList {
+        String getLootId();
+
+        int getAmount();
+
+        boolean getClaimed();
+    }
+}