Add some documentation for SSL_get_shared_ciphers()

=head1 NAME

SSL_get1_supported_ciphers, SSL_get_client_ciphers,

SSL_get_ciphers, SSL_CTX_get_ciphers,

SSL_bytes_to_cipher_list, SSL_get_cipher_list

SSL_get1_supported_ciphers,

SSL_get_client_ciphers,

SSL_get_ciphers,

SSL_CTX_get_ciphers,

SSL_bytes_to_cipher_list,

SSL_get_cipher_list,

SSL_get_shared_ciphers

- get list of available SSL_CIPHERs

=head1 SYNOPSIS

                              int isv2format, STACK_OF(SSL_CIPHER) **sk,

                              STACK_OF(SSL_CIPHER) **scsvs);

 const char *SSL_get_cipher_list(const SSL *ssl, int priority);

 char *SSL_get_shared_ciphers(const SSL *s, char *buf, int size);

=head1 DESCRIPTION

available, or there are less ciphers than B<priority> available, NULL

is returned.

SSL_get_shared_ciphers() creates a colon separated and NUL terminated list of

SSL_CIPHER names that are available in both the client and the server. B<buf> is

the buffer that should be populated with the list of names and B<size> is the

size of that buffer. A pointer to B<buf> is returned on success or NULL on

error. If the supplied buffer is not large enough to contain the complete list

of names then a truncated list of names will be returned. Note that just because

a ciphersuite is available (i.e. it is configured in the cipher list) and shared

by both the client and the server it does not mean that it is enabled (see the

description of SSL_get1_supported_ciphers() above). This function will return

available shared ciphersuites whether or not they are enabled. This is a server

side function only and must only be called after the completion of the initial

handshake.

=head1 NOTES

The details of the ciphers obtained by SSL_get_ciphers(), SSL_CTX_get_ciphers()

=item SSL_SESSION *B<SSL_get_session>(const SSL *ssl);

=item char *B<SSL_get_shared_ciphers>(const SSL *ssl, char *buf, int len);

=item char *B<SSL_get_shared_ciphers>(const SSL *ssl, char *buf, int size);

=item int B<SSL_get_shutdown>(const SSL *ssl);