or-address missing from dir-spec
IPv6 support was added to bridges without its corresponding attribute being added to the directory spec. This is fine, the spec allows for new, unknown fields but ideally this would have been added with the feature.
The snippet to be added is at... https://gitweb.torproject.org/torspec.git/blob/HEAD:/proposals/186-multiple-orports.txt#l111
I'll upload a patch with some minor modifications to that in a sec.
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