## Description
In https://github.com/tendermint/tendermint/pull/4466 a new type was created (EventAttribute) that replaced KV.Pair. This made the type Pair deadcode, this pr removes that type.
I don't think a changelog entry is needed since it is not being used anymore. But will add a section to the upgrading.md to let users know that it was replaced
Closes: #XXX
* Remove omitempty from *pb.go
- remove omitempty from *pb.go files
- added command to makefile for everytime `make protoc_all` is run
- open question:
- Do we want to further remove omitempty from other places
- https://github.com/tendermint/tendermint/blob/master/rpc/lib/types/types.go#L151
- and other places
ref #3882
Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>
* bring back omitempty to *pb.go
* Update types/tx.go
* custom marshlers
* undo benchmark `omitepmty`
* golangci lint fix
* cleanup comments
* changelog_pending entry