ratio handeling in config file

-- CONFIG.LUA FILE---
---------------------

if string.sub(system.getInfo("model"),1,4) == "iPad" then
    print( system.getInfo("model") )
    application =
    {
        content =
        {
            width = 360,
            height = 480,
            scale = "letterBox",
            xAlign = "center",
            yAlign = "center",
            imageSuffix =
            {
                [""] = 1.5,
                ["-hd"] = 3.0,
            },
        },
    }

elseif string.sub(system.getInfo("model"),1,2) == "iP" and display.pixelHeight > 960 then
    print( system.getInfo("model") )
    application =
    {
        content =
        {
            width = 320,
            height = 568,
            scale = "letterBox",
            xAlign = "center",
            yAlign = "center",
            imageSuffix =
            {
                [""] = 1.5,
                ["-hd"] = 3.0,
            },
        },
    }

elseif string.sub(system.getInfo("model"),1,2) == "iP" then
    print( system.getInfo("model") )
    application =
    {
        content =
        {
            width = 320,
            height = 480,
            scale = "letterBox",
            xAlign = "center",
            yAlign = "center",
            imageSuffix =
            {
                [""] = 1.5,
                ["-hd"] = 3.0,
            },
        },
    }
elseif display.pixelHeight / display.pixelWidth > 1.72 then
    print( system.getInfo("model") )
    application =
    {
        content =
        {
            width = 320,
            height = 570,
            scale = "letterBox",
            xAlign = "center",
            yAlign = "center",
            imageSuffix =
            {
                [""] = 1.5,
                ["-hd"] = 3.0,
            },
        },
    }
else
    print( system.getInfo("model") )
    application =
    {
        content =
        {
            width = 320,
            height = 512,
            scale = "letterBox",
            xAlign = "center",
            yAlign = "center",
            imageSuffix =
            {
                [""] = 1.5,
                ["-hd"] = 3.0,
            },
        },
    }
end