Update models with lower case names

Author: nvb

java/hibernate/src/main/java/com/cockroachlabs/model/Customer.java

@@ -3,7 +3,7 @@
 import javax.persistence.*;
 
 @Entity
-@Table(name="Customers")
+@Table(name="customers")
 public class Customer {
 
     @Id

java/hibernate/src/main/java/com/cockroachlabs/model/Order.java

@@ -5,7 +5,7 @@
 import java.util.Set;
 
 @Entity
-@Table(name="Orders")
+@Table(name="orders")
 public class Order {
 
     @Id

java/hibernate/src/main/java/com/cockroachlabs/model/Product.java

@@ -5,7 +5,7 @@
 import java.util.Set;
 
 @Entity
-@Table(name="Products")
+@Table(name="products")
 public class Product {
 
     @Id