Log depot UI changes for FileDepot selection

Changing the LogDepot edit screen to use the FileDepot sub-classes.
I think we're looking if the current protocol matches the last time we set the log_file_depot, right?

Does it make sense to do something like this?
```ruby
@record.log_file_depot.where(:protocol => type).first ||@record.build_log_file_depot(:type => type.to_s)
```

I would suggest to break up this line or create a method for it.  Naming it is hard but it might be worth it so this method can be clearer.