Pike 8.0: Take advantage of the improved SSL support.

Adds support for having multiple certificates for a single port,
and for having password-protected private keys.

NB: Support for SNI will require more changes. This only adds support
for having multiple certificates of different types.
Pike 8.0: Fixed SSL port binding with new API.

ctx->certificates does not get set when the new SSL APIs are used.
This caused SSLProtocol::bind() to fail.

Gets rid of the workaround for the above problem.
Pike 8.0: Upgrade old automatic X.509v1 certs to X.509v3.

Some X.509v3 extensions are supposed to be required in certificates, so
we remake (the old keys are kept) any old automatic certs accordingly.
Merge branch 'patches/pike8.0' into devel

* patches/pike8.0:
  Pike 8.0: Upgrade old automatic X.509v1 certs to X.509v3.
  Pike 8.0: Fixed SSL port binding with new API.
  Pike 8.0: Take advantage of the improved SSL support.

Conflicts:
	server/base_server/roxen.pike