Fix aspect ratio issues, add max-width/max-height options.

[RafaPolit]

Current lightbox implementation has some issues with aspect ratio and margins:

Current buggy behaviors

• Modal imposes a 15px padding right to accommodate the scrollbar. Since this is a no-issue if you are going to force the size to never scroll, this is not required.
• Aspect ratio (when limiting size vertically) is working from a wrong assumption: that aspect ratio of OUTER container should be consistent. This apparently works on larger sizes, but as modal gets smaller, its clear this is the wrong approach: the INNER aspect ratio should match, and it changes having fixed-sizes borders.
• Above 575px the modal has no margins and can touch the borders of the screen, but below that value, a 10px margin is added by bootstrap.

Some missing features

• Modal is not centered on the screen, for image showcase, this is preferable than the normal behavior.
• There is no way to limit the modal to a maximum size. Which could be desirable on scenarios where you have retina-optimized images (2x) that have twice the size as the final desired screen display. (I reported this as issue #273 )

A brief example of the issues:

Notice the higher padding on the bottom and the extra margin on the right.

Proposed fixes

• Modal overrides the 15px padding always to 0.
• Aspect ratio is calculated for the inner space
• Modal always has a 10px separation from the borders
• Modal is centered in the window (taken from #268)
• You can specify a max-width and / or max-height optionally

I have added further example to the index.html examples file.

[ashleydw]

Thanks! :)

[ashleydw]

5.3.0 has been released. When cdnjs updated, I'll update the docs pages 👍