Modifies Ssl & SslContext.
This removes the errors like:
src/ssl/tests.rs:202:14: 202:27 error: the trait `core::kinds::Send` is not implemented for the type `*mut libc::types::common::c95::c_void`
src/ssl/tests.rs:202 let _t = Thread::spawn(move || {
^~~~~~~~~~~~~
src/ssl/tests.rs:202:14: 202:27 note: the type `*mut libc::types::common::c95::c_void` must implement `core::kinds::Send` because it appears within the type `ssl::Ssl`
We may want some locking around calls that do multiple operations on
the underlying Ssl and SslContext objects, but this lets us preserve
functionality for now.