Show every hotel name in the csv file

@gabebw @jsteiner
I think you could rename this method. The method is called `read_file`, but the end result is that it prints hotel names. Maybe `print_hotel_names` instead?

I'd also pass the filename to `initialize`, since it's part of the file's internal state. Each `PropertyQuery` instance needs a `filename` to work, and that filename won't change over the class's lifetime. Therefore, it should be passed to initialize and set to an instance variable.