Specifies the certificate storage where server certificates are stored.
This property defines the certificate storage where TElFTPSServer should take certificate to send to client.
As different ciphersuites require different types of certificates,
it may be impossible to use some ciphersuites due to absence of certificate of
needed type in the storage. If there are no certificates in CertStorage, it's impossible
to use any ciphersuites, except DH_ANON_
Note, that certificates in CertStorage must have corresponding private keys. It is possible to put several certificates without private keys which create a certificate chain, but the ending certificate of the chain must have the private key anyway.