[WIP] Seamless layout

Refs https://github.com/owncloud/gallery/issues/5

![untitled](https://f.cloud.github.com/assets/639688/2491412/9e040be8-b1eb-11e3-9f02-c9414e1f5c28.png)

TODO list:
- [ ] show icon-loading until first pictures are displayed
- [ ] fix opening pictures
- [ ] fix album navigation
- [ ] improve performance