Update base network as combination of enhd, nhdplushr, and merit.
Need to stitch together and normalize everything into a consistently structured reference fabric.
Planning to go in this issue. Can be closed once the workflow and a ready for review gpkg containing the complete set of flowlines is ready.
Include attributes: id, toid (dendritic), fromnode, tonode, divergence, name, lengthkm, totdasqkm, mainstem -- others?
Edited by Blodgett, David L.