tests/test-ui-color.py.out

context: stop setting None for modified or added nodes

Instead use a magic value, so that we can identify modified or added
nodes correctly when using manifest.diff().

Thanks to Martin von Zweigbergk for catching that we have to update
_buildstatus as well. That part eluded my debugging for some time.

warning
error
'buffered\n'
colored? True
colored? True