Update docs w.r.t. maximal number of chars in the file names.

[fkromer]

When one places two files onto the SD card CONFIG.TXT and CONFIGURATION.TXT the later one cannot be read by using this file name cause it "becomes" CONFIG~1.TXT:

SYSTEM~1/     2021-08-26 09:30:02
  WPSETT~1.DAT  2021-08-26 09:30:02 12
  INDEXE~1      2021-08-26 09:30:04 76
CONFIG~1.TXT  2021-08-26 12:06:26 46
CONFIG.TXT    2021-08-26 11:37:26 34

[per1234]

Hi @fkromer. Thanks for taking the time to submit an issue.

I see we already have a prior request for this important enhancement to the documentation at #96.

It's best to have only a single issue per subject so we can consolidate all relevant discussion to one place, so I'll go ahead and close this in favor of the other.

If you end up with additional information to share, feel free to comment in the other thread.