ordinary fucntion remember_Resource instead. Updated all callers.

* src/resource.c (concrete_resource_list): Deleted class, put all
information directly in the resource_lsit class.
(remember_resource): New public function.

Rev: src/channel.c:1.109
Rev: src/channel_forward.c:1.6
Rev: src/client_pty.c:1.22
Rev: src/client_session.c:1.16
Rev: src/client_x11.c:1.18
Rev: src/connection.c:1.71
Rev: src/connection_commands.c:1.41
Rev: src/gateway_commands.c:1.15
Rev: src/gc.c:1.30
Rev: src/io_commands.c:1.50
Rev: src/keyexchange.c:1.85
Rev: src/resource.c:1.25
Rev: src/resource.h:1.14
Rev: src/server_session.c:1.79