Add deprecation messages replaced legacy components (#8584)

* Add deprecation messages replaced legacy components

compatibility-server/src/main/java/com/vaadin/v7/ui/DateField.java

 import com.vaadin.server.PaintException;
 import com.vaadin.server.PaintTarget;
 import com.vaadin.ui.Component;
+import com.vaadin.ui.DateTimeField;
 import com.vaadin.ui.LegacyComponent;
 import com.vaadin.ui.declarative.DesignAttributeHandler;
 import com.vaadin.ui.declarative.DesignContext;
  *
  * @author Vaadin Ltd.
  * @since 3.0
+ *
+ * @deprecated As of 8.0, use {@link com.vaadin.ui.DateField} or
+ *             {@link DateTimeField} instead.
  */
 @SuppressWarnings("serial")
 @Deprecated

compatibility-server/src/main/java/com/vaadin/v7/ui/OptionGroup.java

 import com.vaadin.event.FieldEvents.FocusListener;
 import com.vaadin.server.PaintException;
 import com.vaadin.server.PaintTarget;
+import com.vaadin.ui.CheckBoxGroup;
+import com.vaadin.ui.RadioButtonGroup;
 import com.vaadin.ui.declarative.DesignContext;
 import com.vaadin.ui.declarative.DesignFormatter;
 import com.vaadin.v7.data.Container;
 
 /**
  * Configures select to be used as an option group.
+ *
+ * @deprecated As of 8.0, use {@link RadioButtonGroup} or {@link CheckBoxGroup}
+ *             instead
  */
 @SuppressWarnings("serial")
 @Deprecated