replace errors.go with github.com/pkg/errors (1/2) (#3888)

* (1/2) of replace errors.go with github.com/pkg/errors

ref #3862

- step one in removing instances of errors.go in favor of github.com/pkg/errors

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

* gofmt

* add in /store

store/store_test.go

@@ -9,13 +9,13 @@ import (
 	"testing"
 	"time"
 
+	"github.com/pkg/errors"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	db "github.com/tendermint/tm-db"
 	dbm "github.com/tendermint/tm-db"
 
 	cfg "github.com/tendermint/tendermint/config"
-	cmn "github.com/tendermint/tendermint/libs/common"
 	"github.com/tendermint/tendermint/libs/log"
 	sm "github.com/tendermint/tendermint/state"
 
@@ -53,7 +53,7 @@ func makeStateAndBlockStore(logger log.Logger) (sm.State, *BlockStore, cleanupFu
 	stateDB := dbm.NewMemDB()
 	state, err := sm.LoadStateFromDBOrGenesisFile(stateDB, config.GenesisFile())
 	if err != nil {
-		panic(cmn.ErrorWrap(err, "error constructing state from genesis file"))
+		panic(errors.Wrap(err, "error constructing state from genesis file"))
 	}
 	return state, NewBlockStore(blockDB), func() { os.RemoveAll(config.RootDir) }
 }