urBackup proof of concept

So far I had not tested this solution because it wasn't available by default in the Ubuntu repository. However after my problems with RsyncD on Windows 10, I figured out that maybe another backup solution should be (at least) investigated, just in case backuppc wouldn't do well with Windows backups. I didn't want to go back to SMB backups if I could avoid it. urBackup looks like a nice, open source, polished solution. It is client-based (e.g. a client package has to be installed on each machine to be backed up) but at least it seems to support Windows very well (and I still have to test the Linux client which is essential for my needs). It promises to support backup compression and de-duplication although it is not clear what level of support (at least for compression it relies on the underlying OS and filesystem. Ext4 is not doing that AFAIK). So after adding a PPA, I was able to install a server for testing on kid2. The server configuration was pretty easy (email won't work but that's not urBackup's fault). I downloaded a client on run12l and set it up real quick, then the first backup started. I had to stop it before it could complete, will need to come back to it later.