some styling

playing with the messages view...

- [x] first changes
- [x] invert messages stream as a work around (Xamarin.Forms ListView doesn't allow scroll to bottom)
- [x] show message send time
- [x] prevent selection highlight
- [x] rooms sorting
- [x] rooms styling
- [x] change to theme completely to a white theme http://stackoverflow.com/questions/24102225/changing-the-default-dark-android-theme-to-white-in-xamarin-forms

![2014-11-15 19 39 17](https://cloud.githubusercontent.com/assets/658431/5058826/28ff4cae-6d02-11e4-9e78-88d678ee5b43.png)

![2014-11-14 20 24 25](https://cloud.githubusercontent.com/assets/658431/5052155/26d672fa-6c3e-11e4-8441-28221a41686f.png)