Unify the variable access in the templates.
Extract ca creation to openssl::ca defined type.
Addapt specs for extracted ca creation
Add specs for client mode server.
Add remote parameter to support client mode.
Client mode should have a key directory too.
Add parameters for OpenVPN HA setups.

ping_timer_rem allows to delay timer ticking till a remote clients
connects.
server_poll_timeout allows to set the failover timeout for clients with
multiple servers.