Fix issue mixing %s and format for ValueError in AES
Add method to bindings to get OPENSSL_VERSION_TEXT

* This allows you to check that you're binding against the expected
  version of OpenSSL
* Test is pretty basic (just checks to see that the string starts
  with OpenSSL)
ascii decode on openssl_version_text + doc string improvements
Accurate friendly string name example text
openssl_version_text now calls startswith rather than find
Update docstring to pass alex8 linting
Merge pull request #48 from reaperhulk/master

Add OpenSSL Version Text Method