Core work 2017Q2: Sysadmin (Maintain our already existing services)

Originally created by @intrigeri on #13232 (Redmine)

2017Q2 is almost over, so this is meant to be an example (similar to tails#12431 (closed) & tails#12432 (closed)) to feed the discussion about how we handle time-based core work.

Note: this was reverse-engineered from Puppet Git logs, so it probably lacks lots of work that was done.

Parent Task: tails/accounting#13247

Related issues

• Related to #13233 (closed)
• Blocked by #11523 (closed)
• Blocked by #13134 (closed)
• Blocked by #12414 (closed)
• Blocked by #13138 (closed)
• Blocked by #12565 (closed)
• Blocked by #12097 (closed)
• Blocked by #12422 (closed)
• Blocked by #12425 (closed)
• Blocked by #13177 (closed)