implemented channels on server

tcp-chat-server.toml.default

@@ -1,13 +1,21 @@
+[server]
 name = "Test Server"
 description = """\
     Lorem ipsum labuba aboba.\n\
     Qqqqq...\
     """
-
-landing_channel_id = 0
 local_address = '127.0.0.1:9988'
-db_dir = 'server-db'
-db_aes_key = '<generate with './tcp-chat --random-bytes-base64 32'>'
+landing_channel_id = 0
 
+# do not create channels with the same id
+[channels.general]
+id = 0
+description = "a text channel"
+
+[database]
+dir = 'server-db'
+aes_key = '<generate with './tcp-chat --random-bytes-base64 32'>'
+
+[keys]
 rsa_private_key = '<generate with './tcp-chat --rsa-gen-random'>'
 rsa_public_key = '<copy from output of command above>'