Automatically detect prunable application stores

[sigv]

This removes various dependencies, making the project slimmer, while at the same time allowing it to be more portable across chains (without having to hard-code them). This furthermore eliminates human effort needed at chain upgrades, which may add or remove specific application.db stores.

Worth noting, removal of github.com/cosmos/cosmos-sdk/x/consensus/types package import:

• Closes: Cannot find module providing package #22
• Closes: RocksDB support - "store" module conflict  #23
• Closes: Cannot build the project #29
• Closes: Docker build fails #30

[sigv]

This PR adds rootmulti.GetCommitInfo to keep the change scope as straight-forward as possible.
Upstream Cosmos SDK has already made this function publicly usable in cosmossdk.io/store.

The function added by PR is compatible with the function signature resulting from future rootmulti updates.