Show tiles with different zoom when the correct ones are not available

Hi, I'm using version 0.7.5.0 and loving it :)

The most important usability problem I met using GMapCatcher is that, after 
downloading a country with low zoom level, and some cities with high zoom 
level, it is difficult to navigate in the map.

For example, after looking at the whole country, when I zoom in often I see 
only grey tiles, and to find the city I downloaded I have to zoom out and zoom 
in again.

In this situation, it would be handy to display the low zoom tiles instead of 
just grey. Probably a simple "double every pixel" algorithm could be outclassed 
by an adhoc one, but even the former would be really useful.

Thank you very much for your work, it is really appreciated.

Original issue reported on code.google.com by S.Maggi...@gmail.com on 5 Sep 2010 at 7:35

rishabht1 / gmapcatcher

Show tiles with different zoom when the correct ones are not available #215