Try software for vector tile generation

[klokan]

I believe the right approach for this project is to pre-generate the data into vector tiles which are static - probably saved as PBF files in a folder or packed in SQLite/MBTiles.

The first version can be easily done with Mapbox Studio Classic software: https://www.mapbox.com/mapbox-studio-classic/

@idastorm please install this software and try it with these data:
https://github.com/klokantech/vector-tiles-sample (download and open, esp. countries.tm2source - and try to modify, change data, etc).

Later on we can automate the process of generating vector tiles from the input data on command-line - with TileLive/OpenMapTiles stack or with TippeCanoe.

For raster data (TIFFs) the easiest is to use our MapTiler.

[klokan]

Done already.

Tests in Mapbox Studio Classic - in #9

We have end up using TippeCanoe - via CI (Travis) on GitHub which are automatically building the
vector tiles from the GeoJSON files.

The script calling tippecanoe is visible at:
https://github.com/klokantech/roman-empire/blob/master/task/generate-tiles.sh