Detect retina displays and load the image in the correct size.

https://trello.com/c/4meh4lhV/45-2-detect-retina-display-support-for-mobile-picture-shower

Change-Id: Ie36ef975064fbcd43ec3320d9d78028d9d8d6e17
Merge "Detect retina displays and load the image in the correct size."