core, frontends: various fixes for Libervia:

- quick_app: don't fail when we can't get autodisconnect parameter
    - bridge: removed useless BridgeFrontend parent class
    - use of TypeError, unicode and list to workaround Pyjamas incompatibilities

src/tools/common/ansi.py

@@ -44,7 +44,7 @@ class ANSI(object):
 
 try:
     tty = sys.stdout.isatty()
-except AttributeError:
+except (AttributeError, TypeError):  # FIXME: TypeError is here for Pyjamas, need to be removed
     tty = False
 if not tty:
     # we don't want ANSI escape codes if we are not outputing to a tty!