Tech-savvy, highly-educated, and environmentally conscious, Millennials represent a drastic turn-of-face for the luxury home market — Tatiana and Shannon Harris started their blog — Power Couple Life — as a way to regale followers with glimpses of their lives as luxury travelers, gourmet foodies, and full-time adventurers. After seven years, the couple decided to settle down and purchase a home in Austin, Texas — a city…