Preheat oven to 350 F. In a food processor, add the flours and salt. Pulse until mixed. Add the yogurt, egg white and olive oil and pulse until all incorporated. While pulsing, slowly add the water until a dough comes together. It will be pretty sticky! Spray a pie tin with cooking spray and spatula in the dough. Take a glass cup and spray very well with cooking spray on the bottom (this is an awesome trick to help press down sticky items when cooking). Use the cup to press the dough down and out covering the whole bottom of the tin evenly. Wash and dry the cup, and respray all around the bottom and sides so you can push the dough up along the sides of the pie tin as well. Bake for 10 minutes until crust is firm.