This commit adds the ability to pack preplot points in Dougal
binary format. Sail line points take udv=0 and source line points
take udv=1 – udv=2 remains sequence data.
Endpoints for retrieving the data in JSON, GeoJSON and binary
formats have also been added. Data may be retrieved as a single
line or for a whole project.
Instead of the user giving the recipe for the payload, it now
only handles predefined payload configurations. Those are
denoted by the `type` query parameter. The only valid value
as of this commit is `type=2`.
Look at lib/binary/bundle.js for the definition of a type 2
bundle.