[notmuch] wiki push broken

[Sebastian Spaeth]

git push:
...
Total 3 (delta 2), reused 0 (delta 0)
error: unpack failed: unpack-objects abnormal exit
To git://notmuchmail.org/git/notmuch-wiki
 ! [remote rejected] master -> master (n/a (unpacker error))
error: failed to push some refs to 'git://notmuchmail.org/git/notmuch-wiki'
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This was my test push, certainly nothing that triggers disallowed things:
--- a/index.mdwn
+++ b/index.mdwn 
+## Website
+
 This wiki is maintained using [ikiwiki](http://ikiwiki.info). You can pull and
 push changes using the following URL (no authentication necessary):