Add file deletion functionality
Allow object to have different input and output drivers, so that e.g. we can read from a URL and write to local disk without needing two separate objects
Make more consistent with other drivers: methods accept an E::W::File object as an alternative to a URL, and add "dummy" write & delete methods which return errors if used
Tidy up and add some more inline documentation
Tidy up error-handling
Allow methods to switch between raw mode (for scripts) and non-raw user-friendly mode for web interfaces
Implement raw mode, as per E::W::File::Utils::IO
Update to use values returned by drivers in non-raw mode
All file access methods should take args hashref
Explicitly write to file, because that's what r2r needs in order to do its processing
Most of the time we really only want 'exists' to return a boolean value
Fixed missing semicolon
Make sure that args are always passed into methods