list formats is misleading

[clach04]

On a clean python environment, no encryption is going to be available but:

C:\code\py\puren_tonbo>python -m puren_tonbo.tools.pttkview  --list-formats
2.7.18 (v2.7.18:8d21aa21f2, Apr 20 2020, 13:25:05) [MSC v.1500 64 bit (AMD64)]

Puren Tonbo puren_tonbo version 0.0.dev3
Formats:

           aeszip - PurePyZipAES - AES-256 ZIP AE-1 DEFLATED (regular compression)
       aes256.zip - PurePyZipAES - AES-256 ZIP AE-1 DEFLATED (regular compression)
 aes256stored.zip - ZipNoCompressionPurePyZipAES - AES-256 ZIP AE-1 STORED (uncompressed)
               md - RawFile - Raw file, no encryption support
              txt - RawFile - Raw file, no encryption support
          aes.zip - PurePyZipAES - AES-256 ZIP AE-1 DEFLATED (regular compression)

Libs:
        ccrypt version: MISSING exe: ccrypt

Lists a bunch that are simple NOT available.

Ideas:

1. do better checks
2. consider implementing dumb encryption for testing purposes ONLY. E.g. ROT13 (and ignore password) or simple XOR