Crude file upload support.

Using the carrierwave gem. I can now upload and display a single
picture. I am going to want to use thumbnails instead of displaying
the entire photo. I want to keep thumbnails local and the uploaded
photos in s3.
Added thumbnail support and photo delete
Trips and photos are now partially linked.

This is very ugly, but it should be working. Now I need to show
all of the pictures for a particular trip. Once this is complete
I will rework the code and move things around a bit.