[core/output] Rewrite to hide sys.stout

Add generic "draw()" method that redirects internally to the actual
calls. These can now produce JSON, which is nicer because:

1. Easier to use during testing
2. More flexible
3. Centralizes printing (somewhat)

Still, the "suffix" concept isn't really nice, but so far, I have no
better approach.

modules/test.py

@@ -3,10 +3,11 @@
 """Test module
 """
 
+import core.widget
 import core.module
 
 class Module(core.module.Module):
     def __init__(self):
-        pass
+        super().__init__(core.widget.Widget('test'))
 
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