deploy: Install optional but missing packages

..that snf-* packages do not depend on but deployment requires
(and quick admin install guide mentions).

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
deploy: Move firefox_cert_override.py to Apache

..and install required python-openssl package.

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>