GUACAMOLE-36: Record and maintain password history.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/resources/org/apache/guacamole/auth/jdbc/user/PasswordRecordMapper.xml

@@ -63,7 +63,16 @@
             #{record.passwordHash,jdbcType=BINARY},
             #{record.passwordSalt,jdbcType=BINARY},
             #{record.passwordDate,jdbcType=TIMESTAMP}
-        )
+        );
+
+        DELETE FROM guacamole_user_password_history
+        WHERE password_history_id IN (
+            SELECT password_history_id
+            FROM guacamole_user_password_history
+            WHERE user_id = #{record.userID,jdbcType=INTEGER}
+            ORDER BY password_date DESC
+            OFFSET #{maxHistorySize}
+        );
 
     </insert>