Use SSLv3 by default

SSLv2_client_method may be hidden. Use the SSLv23_client_method instead.

This is a fix from Debian package partimage-0.6.8-2.2.

Signed-off-by: Marko Kohtala <marko.kohtala@gmail.com>
Remove unused variables

gcc 4.8 gives a lot of warnings for unused variable assignments.
Remove or comment out dead code.

Signed-off-by: Marko Kohtala <marko.kohtala@gmail.com>