Add edit and upload photos for a Room

Changelog
========
* Create partial ```_data.html.haml```
* Add edit a room.
* Change ```RMagick``` to ```MiniMagick``` gem.
* Create ```ImageUploader```` for room pictures.
* Add ```lightbox``` js library for show room's pictures.
* Add ```Jquery file upload``` gem to multiple uploads.
* Add upload photos to room.

To use MiniMagick gem we have to install Imagemagick C program.
  * In Ubuntu 12.04 ```sudo apt-get install imagemagick```