Complete rsync.net account migration

New username; separate and longer account manager + storage passwords.

Also, have to use --remote-path=borg1 when interacting with rsync.net.

requested review from @klausenbusk, @jelle, and @svenstaro

To view the current rsync.net passwords: ansible-vault view group_vars/all/vault_rsync.net.yml

As a side effect of the hostname change, our rsync.net username is now public in the same way the Hetzner storage box's is. This implies slightly less security through obscurity but it should make no practical difference.

added 4 commits

• b6d71670...2db513cc - 3 commits from branch master
• 69994e90 - Complete rsync.net account migration

Compare with previous version

mentioned in commit 43c294f4

merged