Particularly:

• bbolt (etcd's fork of bolt) tendermint#3610 (review)
• bbolt (etcd's fork of bolt) tendermint#3610 (comment)
• bbolt (etcd's fork of bolt) tendermint#3610 (comment)
• bbolt (etcd's fork of bolt) tendermint#3610 (comment)

Maybe we should mark boltdb support as highly experimental and not throughly tested in the changelog, too. Also mention where bbolt could be useful (e.g. read-heavy applications?).

ref: tendermint/tendermint#3610, tendermint/tendermint#3611