NNN files

This is my first attempt at creating the NNN files we will require for the
simulation.
This file is the network Kusachi San suggested.
Each Sector's Centor Nodes are connected to neighbor nodes.
Merge pull request #1 from takahiro33/master

This file is the network Kusachi San suggested.
Merge remote-tracking branch 'upstream/master'

Changes made by Kovi, Zhu and Miyamoto for the main line.