proto: add buf and protogen script (#4369)

* proto: add buf and protogen script

- add buf with minimal changes
- add protogen script to easier generate proto files

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* add protoc needs

* add some needed shell cmds

* remove buf from tools as it is not needed everytime

* add proto lint and breakage to ci

* add section in changelog and upgrading files

* address pr comments

* remove space in circle config

* remove spaces in makefile comment

* add section on contributing on how to work with proto

* bump buf to 0.7

* test bufbuild image

* test install make in bufbuild image

* revert to tendermintdev image

* Update Makefile

Co-Authored-By: Anton Kaliaev <anton.kalyaev@gmail.com>

Co-authored-by: Anton Kaliaev <anton.kalyaev@gmail.com>

scripts/protocgen.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+set -eo pipefail
+
+proto_dirs=$(find . -path ./third_party -prune -o -name '*.proto' -print0 | xargs -0 -n1 dirname | sort | uniq)
+for dir in $proto_dirs; do
+  protoc \
+  -I. \
+  --gogo_out=Mgoogle/protobuf/timestamp.proto=github.com/golang/protobuf/ptypes/timestamp,Mgoogle/protobuf/duration.proto=github.com/golang/protobuf/ptypes/duration,plugins=grpc,paths=source_relative:. \
+  $(find "${dir}" -name '*.proto')
+done