Customer Ethernet Cable
You have 2 options to wire the Raspberry PI units.
use seperate Micro USB power Cable and Ethernet Cable. This does require 2x more cables, but allows you to use off the self products.
You can make a customer CAT5 ethernet cable that can be used for both Ethernet and Power. 100MB ethernet only uses 4 of the 8 cables in a CAT5/6 cable. So you can use the other 2 or 4 (bundled) cables for the 5v power for the raspberry.