Point to GitHub's deploy keys docs and add info on server SSH keys

doc/README.md

@@ -0,0 +1,11 @@
+# Hosted
+
+Repomaker can be run on a server in hosted mode.
+Set `SINGLE_USER_MODE` to `False` in the settings.
+
+## Enabling Remote Storage
+
+Publishing to remote storages uses SSH.
+For this to work, the user running the background tasks
+needs to have the remote server's key in its  `.ssh/known_hosts` file.
+

repomaker/templates/repomaker/storage/detail_git.html

@@ -8,7 +8,7 @@
 	There are instructions for
 	<a href="https://docs.gitlab.com/ee/gitlab-basics/create-your-ssh-keys.html#how-to-create-your-ssh-keys">Gitlab</a>
 	and
-	<a href="https://help.github.com/articles/adding-a-new-ssh-key-to-your-github-account/">GitHub</a>.
+	<a href="https://developer.github.com/v3/guides/managing-deploy-keys/#deploy-keys">GitHub</a>.
 	{% endblocktrans %}
 </p>
 <p>