Add illustrations to the warning pop-ups

[nicolas-raoul]

We have many different possible warnings.
When uploading many pictures very quickly, there can be popup fatigue, meaning the user does not even read the message anymore.

If there was an illustration in the popup, the user would more reliably recognize the warning even at high speeds. For instance, in the middle of uploading 100 pictures without EXIF, the user would still react correctly if a "already on Commons" popup suddenly shows up, and would not skip it mechanically.

The illustrations should be compatible with our license, public domain is fine.

[dohyun123]

I'm a computer science major interested in contributing to open source. Could you assign this issue to me?

[nicolas-raoul]

@dohyun123 Sorry would you mind using the "unassigned bug" link at https://github.com/commons-app/commons-app-documentation/blob/master/android/Volunteers-welcome!.md#developers to find an issue to work on? Thanks a lot! :-)