www/node8: copy from www/node, update 8.8.1 -> 8.9.0 (LTS)
Create a new port for the latest Node.js 8.9.0 LTS release. Update
CONFLICTS for the existing Node.js ports to include the new node8
port and remove non-existent ports.
https://nodejs.org/en/blog/release/v8.9.0/