Use stricter getIsImage() check in AssetAdmin
Use stricter getIsImage() check in AssetAdmin

Folder and File also have a getWidth() and getHeight() method because it's on the base class

silverstripe/silverstripe-asset-admin,open-sausages/silverstripe-asset-admin,open-sausages/silverstripe-assets-gallery,open-sausages/silverstripe-assets-gallery,silverstripe/silverstripe-asset-admin,open-sausages/silverstripe-asset-admin