implement frame buffer fetch extension for iOS, change composition on stroke drawing and commit, add rename layer dialog

PanoPainter/AppDelegate.m

@@ -7,6 +7,7 @@
 //
 
 #import "AppDelegate.h"
+#include "app.h"
 
 @interface AppDelegate ()
 
@@ -32,10 +33,12 @@
 
 - (void)applicationWillEnterForeground:(UIApplication *)application {
     // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
+    App::I.redraw = true;
 }
 
 - (void)applicationDidBecomeActive:(UIApplication *)application {
     // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
+    App::I.redraw = true;
 }
 
 - (void)applicationWillTerminate:(UIApplication *)application {