Python and Perl scripts: Print warnings, errors and usage to stderr

[magnumripper]

Also add missing newlines to some python calls to sys.*.write.

Usage to stderr isn't always the norm but in this case we're normally running redirected to file and the usage blob may be caused by options/syntax problems.

[solardiz]

The changes look good to me, but seem incomplete. At least this is still missing the newlines:

fvde2john.py:    sys.stderr.write("cryptography is missing, run 'pip install --user cryptography' to install it!")
fvde2john.py:    sys.stderr.write("pytsk3 is missing, run 'pip install --user pytsk3' to install it!")
fvde2john.py:        sys.stderr.write("Error reading out of bounds of file, exiting.")
fvde2john.py:        sys.stderr.write(f"[!] Invalid sector size {sector_size} (not 512 or 4096 bytes). Exiting.")
fvde2john.py:            sys.stderr.write("[!] No CoreStorage volumes found, exiting.")

[magnumripper]

Oh, I fixed those but dropped/postponed it because of #5895. I see now I even mentioned it in #5900 (comment).

I'll fix them and add here. I'll also retry some grep-fu.

[magnumripper]

Will add yet some to this, I found more.

[magnumripper]

I'm still working on this one. It must be rebased onto #5931 once that one is merged.

[magnumripper]

I'm still working on this one. It must be rebased onto #5931 once that one is merged.

Done now. Apparently we can merge this before or after #5931.