CoinDaemon: support multiple daemons per coin

- specify the daemon via the --daemon-id option

mmgen/daemon.py

@@ -345,7 +345,12 @@ def __new__(cls,
 			coin,network = CoinProtocol.Base.parse_network_id(network_id)
 			coin = coin.upper()
 
-		daemon_id = cls.coins[coin].daemon_ids[0]
+		daemon_ids = cls.coins[coin].daemon_ids
+		daemon_id = g.daemon_id or daemon_ids[0]
+
+		if daemon_id not in daemon_ids:
+			die(1,f'{daemon_id!r}: invalid daemon_id - valid choices: {fmt_list(daemon_ids)}')
+
 		me = Daemon.__new__(globals()[daemon_id + '_daemon'])
 		assert network in me.networks, f'{network!r}: unsupported network for daemon {daemon_id}'
 		me.network = network

mmgen/globalvars.py

@@ -151,6 +151,7 @@ class GlobalContext(Lockable):
 	)
 	data_dir_root,data_dir,cfg_file = None,None,None
 	daemon_data_dir = '' # set by user
+	daemon_id = ''
 
 	# global var sets user opt:
 	global_sets_opt = (
@@ -166,7 +167,7 @@ class GlobalContext(Lockable):
 		'rpc_host','rpc_port','rpc_user','rpc_password','rpc_backend','aiohttp_rpc_queue_len',
 		'monero_wallet_rpc_host','monero_wallet_rpc_user','monero_wallet_rpc_password',
 		'daemon_data_dir','force_256_color','regtest','coin','bob','alice',
-		'accept_defaults','token','ignore_daemon_version'
+		'accept_defaults','token','ignore_daemon_version','daemon_id'
 	)
 	# opts initialized to None by opts.init() if not set by user
 	required_opts = (

mmgen/opts.py

@@ -188,6 +188,7 @@ def do_fmt(set_data):
 --, --force-256-color      Force 256-color output when color is enabled
 --, --data-dir=path        Specify {pnm} data directory location
 --, --daemon-data-dir=path Specify {dn} data directory location
+--, --daemon-id=ID         Specify the coin daemon ID
 --, --ignore-daemon-version Ignore {dn} version check
 --, --no-license           Suppress the GPL license prompt
 --, --rpc-host=host        Communicate with {dn} running on host 'host'