#1618 AES-256: no such method

[Sam Tansy]

I got this encrypted zip which old unzip couldn't handle. Close inspection with `7z -l -slt' option said it was `AES-256', not `ZipCrypto' method. Then trying to emulate this method i got an error.

 $ 7z a -p"pass" -mem=AES-256 secret.AES-256.zip secret.txt
 (...)
System ERROR:
E_INVALIDARG

After digging the internet and documentation it turned out it is not `AES-256' but `AES256'. which is confusing to say the least.
Could the be called in listing as they are in method call?

[Igor Pavlov]

I'll fix that thing.
Actually it also supports -mem=aes now.