Replaced hard coded SSL_VERSIONS for introspecting into OpenSSL SSL_VERSIONS.
Replaced hard coded SSL_VERSIONS for introspecting into OpenSSL SSL_VERSIONS.

- Doing it this way makes HTTPI compatible with Ruby 1.9.x-2.1.x
- It will automatically pick up newer TLS versions.

mbrung/httpi,sobrinho/httpi,savonrb/httpi,liftforward/httpi