console.py: can now connect to several daemons/wallets

Also throw exceptions instead of print+exit, since that makes
the error print last, below the python stack trace, where it's
much less easy to miss it.

utils/python-rpc/framework/daemon.py

@@ -33,6 +33,8 @@ from .rpc import JSONRPC
 class Daemon(object):
 
     def __init__(self, protocol='http', host='127.0.0.1', port=0, idx=0):
+        self.host = host
+        self.port = port
         self.rpc = JSONRPC('{protocol}://{host}:{port}'.format(protocol=protocol, host=host, port=port if port else 18180+idx))
 
     def getblocktemplate(self, address, prev_block = ""):