Enabling TLS1.2 support

Unfortunately OS X comes with 0.9.8 bundled. There is a way to
install a recent version through homebrew, however it is
extremely hard to make it link agains brewed version without
tricking link version
Simplified manifest
Allow to set cert/key pair
Allow SSL stream cloning, buffer separation

Only if original stream is clonnable
Allows to use SSL stream from multiple threads:
primary goal is to allow 2 different threads to
be used for only reading and only writing. It
may be pretty fragile, but at least it should
be tried