Upgrade lizard's storage (2017 edition)

Originally created by @intrigeri on #13425 (Redmine)

Given what tails#12002 (closed) and #11806 (closed) taught us, and the painful situation we’re in already wrt. storage, we need to upgrade lizard’s storage ASAP as a first step towards #11680 (closed), without figuring out the rest of #11680 (closed) yet. Whatever storage we add can be reused when we do #11680 (closed) anyway :)

Setting target version = 3.1 because such things take time, so better start early if we want to get it done within a reasonable time frame.

Parent Task: #11680 (closed)

Related issues

• Related to #13526 (closed)
• Related to #14732 (closed)
• Related to #14797 (closed)
• Blocked by #11806 (closed)
• Blocks #12595 (closed)