#61 add basic working search within Poland's bounds

[sabman]

Work for #61

[jsanz]

@Mordechai23 @sabman not sure if you are accepting reviews and other types of contributions, but if it helps in any way, I've tested this PR and the search bar renders without issues and accepts inputs in several languages, nice job!

[pmatejko]

I also tested it and it looks like a nice feature, thanks for contribution :)

[jsanz]

Would it make sense to do a follow up enhancement for this feature adding results to the search bar coming from the vector layers in the overlay?

I don't know if it's useful, if all vector data is coming from OSM, hence nominatim would pick up the same results anyways.

[Mordechai23]

I don't know if it's useful, if all vector data is coming from OSM, hence nominatim would pick up the same results anyways.

The donation drop points layer

contains manually added data, not present in OSM (It wouldnt make sense to add those points there anyway) . I tried to keep it compatible with the osm-style tagging, so they have attributes like name=* , description=* , addr=* , etc.

Possibility to search for it would be really nice