Support for Media Files

This release includes full support for uploading and downloading media files!

await Client.UploadAsync(new MediaUpload
{
	Product =
	{
		Identifier = "nike_air",
		Locale = Locales.EnglishUs,
		Scope = AkeneoDefaults.Channel,
		Attribute = "product_logotype"
	},
	FilePath = "C:\\tmp\\swoosh.png",
	FileName = "nike_logo.png"
});
var mediaInfo = await Client.DownloadAsync("a/a/dsad/swoosh.png");
mediaInfo.WriteToFile("C:\\tmp");