Revert "remove tombstones" (#430)

* Revert "remove tombstones (#426)"

This reverts commit aa6bab40.

* tombstones don't hide storage or account anymore

* auto-format code by prettier (similar to gofmt)

* wow, it works.....

* small simplification, but need make it more clear

* rebase to master

* rebase to master

* rebase to master

* re-run ci

* clean test files