Fixed cipher to aes-256-cbc. Remove size and mode init options. changed key derivation to use pbkdf2 instead of keyivgen. Compatibility spec with openssl is not fully working because for some reason command line openssl attaches some funky non-utf-8 string to the begining of the decrypted text, though the text is decrypted correctly.  The crazy part is that the length of this appendix varies so i'm not sure how to trim it because i couldn't figure out how it depends on the salt and iv, so made the tests pass by just matching the string