Add currency symbol

Author: ul-jf

src/main/java/io/ipgeolocation/api/GeolocationCurrency.java

@@ -5,10 +5,12 @@
 public class GeolocationCurrency {
     private String name;
     private String code;
+    private String symbol;
 
     GeolocationCurrency(Map json) {
         this.name = (String) json.get("name");
         this.code = (String) json.get("code");
+        this.symbol = (String) json.get("symbol");
     }
 
     public String getName() {
@@ -19,8 +21,12 @@ public String getCode() {
         return code;
     }
 
+    public String getSymbol() {
+        return symbol;
+    }
+
     @Override
     public String toString() {
-        return String.format("name: '%s' \ncode: '%s'", name, code);
+        return String.format("name: '%s' \ncode: '%s' \nsymbol: '%s'", name, code, symbol);
     }
 }