[4/30] Modifications to picture upload script to accommodate image sizes up to 200...

[4/30] Modifications to picture upload script to accommodate image sizes up to 200 X 300 pixel dimesions.

This also changes the storage image format to PNG which is lossless (an important factor when using these
images for patroncards).

NOTE: In the end, this script was *not* used for uploading images for patron cards. However, these changes
are left as an improvement upon this script which is used for patron image uploads.

This script could be greatly reduced in size by using Graphics::Magick and working along the same lines
as the upload code found in patroncards/image-manage.pl