[OSM-dev] Lite OSM backend

[Nicola Ranaldo]

> Oliver has probably thought of this, but there are substantial further
> savings using offsets.

To have a plug&play binary file we need indexes on lat/lon to fast filter 
bounding boxes.  We could release two packages, data only or data + indexes. 
Users could choose and run the full package or the partial (generating 
indexes offline).

About flags, i think 32 bits are not sufficient. We should think about a 
system to extend tags. For example if the  32th is set to 1 then software may 
lookup a special file to find the other tags.
To avoid a large use of this overload area, generating tools should sort tags 
by usage, assign the 31 most used to bits and generate a configuration file 
to get mapping.

	Niko