Read files by name from dump, if they are not visible in list_filesystem

[SciLor]

If the flash has been written several times, list_filesystem will lose the ability to read the filenames. If you read those files via UART some magic on the cc3200 is done, so the files are found even in that state. If you are using a flashdump this doesn't work. You may dump the file by index in that case.

So we need to find out what this magic does and implement it inside the tool.

[SciLor]

File could not be read, [Errno 21] Is a directory: 'path/' occurs on all files without a name