Implement our backup plan

[jesusaurus]

Implement our backup plan

[jesusaurus]

This is being implemented in BonnyCI/hoist#335

[jesusaurus]

• [x] Create ansible roles for backup clients and server
• [x] Configure list of backup source directories
• [x] Allow backups to happen at various times and intervals
• [x] Test restoring from backup
• [x] Delete expired backups

[jasontclark]

Added myself from a documentation perspective.

[jesusaurus]

Restoring from backup does not remove files not in the backup, it only affects files in the archive.

I think this is fine for now, and if we decide we want to purge files not in the archive we can add that as a task in the restore playbook.

[jesusaurus]

I think we can call this done