* ext/openssl/ossl_cipher.c (ossl_s_ciphers): new method
  OpenSSL::Cipher.ciphers. it returns all the cipher names.

* ext/openssl/ossl_cipher.c (ossl_cipher_init): refine warning message.

* ext/openssl/lib/openssl/cipher.rb: reimplement without eval() and
  add constants AES128, AES192, AES256. [ruby-dev:28610]

* ext/openssl/lib/openssl/digest.rb: reimplement without eval().

* test/openssl/test_cipher.rb, test_digest: fix about reimplemented               features.

* sample/openssl/cipher.rb: rewrite all.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@10137 b2dd03c8-39d4-4d8f-98ff-823fe69b080e