localrepo: remove all internal uses of localrepo.opener It has been replaced with localrepo.vfs. In the future we may split the vfs into different vfs objects to access different elements of the repository.

sslutil: drop defunct ssl version constants Nobody outside sslutil should be using these constants anyway.

sslutil: use saner TLS settings on Python 2.7.9 Asking for TLSv1 locks us out of TLSv1_2 etc. This is at least less bad. Ideally we'd use ssl.create_default_context(), but that causes more mayhem in the testsuite than I really want to deal with right now.