Problems with image fitting

[tsujan]

With this issue, I start to tell about lximage-qt problems I've found over years (sorry that I can't use the issue template for this).

• The images fitting isn't preserved when you make a big image full-screen and then un-full-screen. (Fixed)

• There is no indication in the GUI about fitting. You should guess that by seeing the image and you might be wrong.

• Fitting by enlarging (I call it "Force Fitting") doesn't exist. It's useful especially with small SVG images.

• Fitting without keeping proportions is missing. It's useful when, for example, you want to see how a nature image will look like as your wallpaper. Keeping the proportions isn't important for all kinds of images.

• The current toolbar design isn't handy (fitting is between other buttons):

  

  "Original size" should be beside zoom buttons, zoom buttons should be separated from other buttons,..., like this (not a screenshot of lximage-qt):

  

I might add other cases to the list later.