Correct additional PHP Notice logs

[lat9]

Correct various PHP Notice logs generated during Tools->Image Handler processes.

[lat9]

On initial entry to Tools->Image Handler, the following notices are thrown:

[03-Jul-2019 07:29:52 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php, IP address: ::1
--> PHP Notice: Undefined variable: product in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php on line 358.

[03-Jul-2019 07:29:52 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php, IP address: ::1
--> PHP Notice: Trying to get property of non-object in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php on line 358.

[lat9]

After selecting a product with no images:

[03-Jul-2019 07:40:11 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php?products_filter=218&action=layout_new, IP address: ::1
--> PHP Notice: Undefined variable: selected_image_name in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php on line 719.

[03-Jul-2019 07:40:11 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php?products_filter=218&action=layout_new, IP address: ::1
--> PHP Notice: Undefined variable: selected_image_extension in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php on line 719.

[03-Jul-2019 07:40:11 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php?products_filter=218&action=layout_new, IP address: ::1
#1  boxTableBlock->tableBlock() called at [C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\includes\classes\box.php:41]
#2  box->infoBox() called at [C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php:809]
--> PHP Notice: Undefined index: text in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\includes\classes\table_block.php on line 61.

[lat9]

Submitting a 'new image' with all fields left blank:

[03-Jul-2019 08:00:41 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php?products_filter=218&&action=save, IP address: ::1
#1  require(C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\includes\ih_manager.php) called at [C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php:86]
--> PHP Notice: Undefined index: imgBase in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\includes\ih_manager.php on line 308.

[03-Jul-2019 08:00:41 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php?products_filter=218&&action=save, IP address: ::1
--> PHP Notice: Undefined variable: hidden_vars in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php on line 752.

[lat9]

Deleting an image without checking the "Remove from database only" box:

[03-Jul-2019 08:51:08 America/New_York] Request URI: /zc156posm/gRoan-Dsw-Habit/image_handler.php?products_filter=218&action=delete, IP address: ::1
#1  require(C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\includes\ih_manager.php) called at [C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\image_handler.php:86]
--> PHP Notice: Undefined index: delete_from_db_only in C:\xampp\htdocs\zc156posm\gRoan-Dsw-Habit\includes\ih_manager.php on line 457.