update the devices it works with

fix some text and comments
shorten some if conditions
I did not merged this. I added it because it is necessary in these rare cases.
For some devices (I don't know why) `new File(null)` is executed if there is no return statement.
`new File(null)` will lead to a crash. Please see: https://github.com/ikarus23/MifareClassicTool/commit/4ed5a71b6bf8d473b78bdd416063c4dc1e5644bf