Fork geobuf 1.0 to create topobuf

[maurizi]

geobuf used to support (de)serializing TopoJSON in addition to GeoJSON in version 1, but this was removed in version 2+ and now it only supports GeoJSON: https://github.com/mapbox/geobuf/issues/43

We should fork the library at 1.0.1, remove the support for GeoJSON, and publish it on npm under the name topobuf (assuming it's available still).

AC:

• Fork the library @ 1.0.1
• Enable Travis CI
• Remove support for GeoJSON from the project
• Remove bin/ CLI files
• Rename geobuf -> topobuf in the entire project
• Add type declarations (see https://www.typescriptlang.org/docs/handbook/declaration-files/publishing.html#including-declarations-in-your-npm-package)
• Update the README
• Publish to NPM as topobuf version 1.0.0

[maurizi]

This is done https://www.npmjs.com/package/topobuf