topics: add a config to reject draft changeset without topic on a server This patch adds a new config option experimental.topic-mode.server which if sets to True, the server won't accept any draft changeset without topic on it. In case both `experimental.topic-mode.server` and `experimental.topic.publish-bare-branch` are set to True, the enforce-topic one is respected. Tests are added for it. The CHANGELOG file is also updated mentioning about the config option.

#!/bin/sh
sleep 5
echo "new desc" >> $1