libs/common: refactor libs/common 2 (#4231)

* libs/common: refactor libs/common 2

- move random function to there own pkg

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

* change imports and usage throughout repo

* fix goimports

* add changelog entry

abci/client/socket_client_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/tendermint/tendermint/abci/server"
 	"github.com/tendermint/tendermint/abci/types"
 	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/tendermint/tendermint/libs/rand"
 )
 
 func TestSocketClientStopForErrorDeadlock(t *testing.T) {
@@ -96,7 +97,7 @@ func TestHangingSyncCalls(t *testing.T) {
 func setupClientServer(t *testing.T, app types.Application) (
 	cmn.Service, abcicli.Client) {
 	// some port between 20k and 30k
-	port := 20000 + cmn.RandInt32()%10000
+	port := 20000 + rand.RandInt32()%10000
 	addr := fmt.Sprintf("localhost:%d", port)
 
 	s, err := server.NewServer(addr, "socket", app)

abci/example/kvstore/helpers.go

@@ -2,14 +2,14 @@ package kvstore
 
 import (
 	"github.com/tendermint/tendermint/abci/types"
-	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/tendermint/tendermint/libs/rand"
 )
 
 // RandVal creates one random validator, with a key derived
 // from the input value
 func RandVal(i int) types.ValidatorUpdate {
-	pubkey := cmn.RandBytes(32)
-	power := cmn.RandUint16() + 1
+	pubkey := rand.RandBytes(32)
+	power := rand.RandUint16() + 1
 	v := types.Ed25519ValidatorUpdate(pubkey, int64(power))
 	return v
 }

abci/tests/server/client.go

@@ -7,15 +7,15 @@ import (
 
 	abcicli "github.com/tendermint/tendermint/abci/client"
 	"github.com/tendermint/tendermint/abci/types"
-	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/tendermint/tendermint/libs/rand"
 )
 
 func InitChain(client abcicli.Client) error {
 	total := 10
 	vals := make([]types.ValidatorUpdate, total)
 	for i := 0; i < total; i++ {
-		pubkey := cmn.RandBytes(33)
-		power := cmn.RandInt()
+		pubkey := rand.RandBytes(33)
+		power := rand.RandInt()
 		vals[i] = types.Ed25519ValidatorUpdate(pubkey, int64(power))
 	}
 	_, err := client.InitChainSync(types.RequestInitChain{