Remove 3 decimals rule on currency due to 3 dec in taxes. Keep decimals separate. Add default tax dec in tables (#327)

database/database.sql

@@ -60,6 +60,7 @@ INSERT INTO `ospos_app_config` (`key`, `value`) VALUES
 ('currency_symbol', '$'),
 ('decimal_point', '.'),
 ('currency_decimals', '2'),
+('tax_decimals', '2'),
 ('quantity_decimals', '0');
 
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