I agree that the RX 480 will be better in the future and last you longer than the GTX 1060. Supports crossfire ( Which is very scalable with AMD right now) , has more Vram support, and supports Vulcan / DX 12 which leave the GTX 1060 6GB in the dust.
Overall if you can get the RX 480 8GB then i would . GTX 1060 is good for older games.