Less intrusive download prompt

[Markus40]

The download prompt is quite big and intrusive. There are two seperate problems:

1. The prompt makes it hard to navigate at map borders because the prompt will immediately appear when the center is outside of the downloaded map region.

2. When world map with high zoom levels will be available the prompt will take up a lot of screen space.

Possible solutions:

• Make the prompt appear if the middle of the screen is a certain distance from map edge or if a certain amount of the screen surface area is not covered by a downloaded map.
• Make the prompt appear only over the downloadable area (ancored to the map, not the screen)
• Move downloaded prompt out of the way, make it smaller, make it partly transparent

[matkoniecz]

When world map with high zoom levels will be available the prompt will take up a lot of screen space.

But it does not exist now, right? Is it even likely to be added? This seems purely theorethical.

(and making prompt harder to notice may be problematic in other ways - with users not noticing it and being confused why map has no info)

[Misalf-git]

OsmAnd prompts with a banner at the top of the screen. Still very visible without blocking the view.