Add initial structure of BatchBuilder

batchbuilder/batchbuilder_test.go

@@ -0,0 +1,18 @@
+package batchbuilder
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/iden3/go-merkletree/db/memory"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestBatchBuilder(t *testing.T) {
+
+	stateDB := memory.NewMemoryStorage()
+
+	bb, err := NewBatchBuilder(stateDB, nil, 0, 0, 32)
+	assert.Nil(t, err)
+	fmt.Println(bb)
+}