add optimistic locking for savings account

mifosng-provider/src/main/java/org/mifosplatform/portfolio/savings/domain/SavingsAccount.java

@@ -49,6 +49,7 @@ import javax.persistence.Temporal;
 import javax.persistence.TemporalType;
 import javax.persistence.Transient;
 import javax.persistence.UniqueConstraint;
+import javax.persistence.Version;
 
 import org.apache.commons.lang.ObjectUtils;
 import org.apache.commons.lang.StringUtils;
@@ -105,6 +106,9 @@ import com.google.gson.JsonArray;
 @DiscriminatorValue("100")
 public class SavingsAccount extends AbstractPersistable<Long> {
 
+    @Version
+    int version;
+
     @Column(name = "account_no", length = 20, unique = true, nullable = false)
     protected String accountNumber;
 

mifosng-provider/src/main/resources/sql/migrations/core_db/V221__add_version_for_m_savings_account.sql

@@ -0,0 +1,2 @@
+ALTER TABLE `m_savings_account`
+	ADD COLUMN `version` INT(15) NOT NULL DEFAULT '1' AFTER `on_hold_funds_derived`;