If a text editor creates hidden save files, those will get copied into
the ROMFS. This is now fixed by deleting hidden files.
Also, the there was some available potential by removing the leading
whitespace.
When we open the file handle to write back the lines in binary mode, we don't change the line endings but instead leave them as they were before. This is impotant for Windows users as Python on Windows otherwise adds CRLF endings to the parameter files and they can't be correctly parsed by NuttX any more.