Client for playing 300 publicly available Sokoban puzzles on a computer or phone.
directory_contents = function(directory)
	contents = {}
	local filenames = App.files(directory)
	for _,filename in ipairs(filenames) do
		local file_info = App.file_info(directory..filename)
		if file_info.type == 'file' then
			table.insert(contents, filename)
		end
	end
	table.sort(contents)
	return contents
end