Corrected paths for image and audio files in the DB
Change the relative path for narratives, image and audio (remove public)
Images display in the proper order when a narrative is played. A default image is displayed if the narratives has no images.
For now, the default image is just a random image taken from the internet.
Note: Right now the case where we have audio files 1, 2, 3, 4... but only image file 5.jpg is not handled properly (the default image is currently displayed).
Changes to admin_controller to respect the new pathname scheme.
Merge branch 'backend-dev' of https://github.com/felixsoum/youdeliberate into backend-dev
Fixed bug where a narrative with audio files 1 to 4 and only one image file (5), would display the default image instead of image file 5.
Add corresponding comments to narratives, fix the progress bar for audio and volume
Merge pull request #18 from felixsoum/backend-dev

Backend dev
Merge branch 'frontend' into backend

Conflicts:
	app_60/app/controllers/narratives_controller.rb
	app_60/app/views/narratives/play.html.erb
	app_60/db/development.sqlite3
Merge pull request #19 from felixsoum/backend

Integrate backend and frontend into master