Loupe 49.2

- Check if the is-hidden property is available before reading it.
- Considerably increased speed for listing other images in folders, especially for remote locations. This allows for switiching to other images to become available much quicker.
- Fix panics, probably occuring when using an action like 'copy', and then closing the window. The crash causes all other windows to close. #553
- Force gufo-exif version 0.3.1 to fix the missing beginning of user comments.
- Showing wrong mime type in error message if the file ending for an image is wrong.
- The creation date for images that don't provide a timezone was displayed as if the recorded date and time was in UTC.
- Zooming in would not work via the zoom menu, if the resulting zoom state would still fit the image inside the window.

- Track the location in source code of errors trying to get the root window.

Git-EVTag-v0-SHA512: 3084eba781b6390e0ed08326fb81f648736fc2fe3417abcbd593dd66126c7ea06aa0b0bd216d749df49ae15ee3a708d5c9e0d48066be8699dd590d31aaa15b67