Use doubles for tax amount in config instead of int (Fixes #578)

For some reason this already was a float internally but not exposed in the config? Wat.

src/main/java/com/Acrobot/ChestShop/Configuration/Properties.java

@@ -190,10 +190,10 @@ public <T> Object parseToJava(Class<T> type, Object object) {
     public static UUID SERVER_ECONOMY_ACCOUNT_UUID = new UUID(0, 0);
 
     @ConfigurationComment("Percent of the price that should go to the server's account. (100 = 100 percent)")
-    public static int TAX_AMOUNT = 0;
+    public static double TAX_AMOUNT = 0;
 
     @ConfigurationComment("Percent of the price that should go to the server's account when buying from an Admin Shop.")
-    public static int SERVER_TAX_AMOUNT = 0;
+    public static double SERVER_TAX_AMOUNT = 0;
 
     @ConfigurationComment("Amount of money player must pay to create a shop")
     public static BigDecimal SHOP_CREATION_PRICE = BigDecimal.valueOf(0);

src/main/java/com/Acrobot/ChestShop/Listeners/Economy/TaxModule.java

@@ -20,8 +20,8 @@ public class TaxModule implements Listener {
     private static final String TAX_RECEIVED_MESSAGE = "Applied a tax of %1$f percent (%2$.2f) to the received amount for a resulting price of %3$.2f";
     private static final String TAX_SENT_MESSAGE = "Reduced buy price by tax of %1$f percent (%2$.2f) for a resulting price of %3$.2f as the buyer has the buy tax bypass permission";
 
-    private static float getTax(UUID partner) {
-        float taxAmount = NameManager.isAdminShop(partner) || NameManager.isServerEconomyAccount(partner)
+    private static double getTax(UUID partner) {
+        double taxAmount = NameManager.isAdminShop(partner) || NameManager.isServerEconomyAccount(partner)
                 ? Properties.SERVER_TAX_AMOUNT : Properties.TAX_AMOUNT;
 
         if (taxAmount == 0) {
@@ -31,7 +31,7 @@ private static float getTax(UUID partner) {
         return taxAmount;
     }
 
-    private static BigDecimal getTaxAmount(BigDecimal price, float taxAmount) {
+    private static BigDecimal getTaxAmount(BigDecimal price, double taxAmount) {
         return price.multiply(BigDecimal.valueOf(taxAmount)).divide(BigDecimal.valueOf(100), Properties.PRICE_PRECISION, BigDecimal.ROUND_HALF_UP);
     }
 
@@ -41,7 +41,7 @@ public static void onCurrencyTransfer(CurrencyTransferEvent event) {
             return;
         }
 
-        float taxAmount = getTax(event.getPartner());
+        double taxAmount = getTax(event.getPartner());
         if (taxAmount == 0) {
             return;
         }