function onWrite( error ) {
		if ( error ) {
			debug( 'Encountered an error when writing file contents. File: %s (%d of %d). Destination: %s. Error: %s', file, i+1, total, fpath, error.message );
			return clbk( error );
		}
		debug( 'Successfully wrote file.' );
		done();
	}
Callback invoked after writing a file.

@private
@param {Error} [error] - error object
@returns {void}