Implement new session functions

[enkore]

Functions replacing deprecated functions are missing:

• Session:
  • is_server_known -> is_known_server
  • dump_knownhost -> export_known_hosts_entry
  • write_knownhost -> update_known_hosts

Some constants are missing

• SSH_LOG_xxx (for SSH_OPTIONS_LOG_VERBOSITY; Workaround: use SSH_OPTIONS_LOG_VERBOSITY_STR)

This is pretty minor stuff, not sure if it is even worth addressing.

(eref 42d478fb6976)

[pkittenis]

Thanks for interest and report.

SSH_LOG_ have been implemented, not released yet - see #30.

PR welcome for the session functions.