[core/output] Implement autohide

Allow output to automatically hide widgets that are *not* in any
critical mode

core/config.py

@@ -39,4 +39,7 @@ class Config(util.store.Store):
     def iconset(self):
         return self._args.iconset
 
+    def autohide(self, name):
+        return name in self._args.autohide
+
 # vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4

core/output.py

@@ -93,6 +93,9 @@ class i3(object):
     def widgets(self, module):
         widgets = []
         for widget in module.widgets():
+            if self._config.autohide(widget.module().name()):
+                if not any(state in widget.state() for state in [ 'warning', 'critical']):
+                    continue
             widgets += self.__separator(module, widget)
             widgets += self.__main(module, widget, self._status[widget])
             core.event.trigger('next-widget')