new game, fs repo layer

pkg/repo/repo.go

@@ -0,0 +1,27 @@
+package repo
+
+import "github.com/iliadenisov/galaxy/pkg/repo/fs"
+
+type Storage interface {
+	Lock() (func() error, error)
+	Write(string, []byte) error
+}
+
+type repo struct {
+	s Storage
+}
+
+func NewRepo(s Storage) (*repo, error) {
+	r := &repo{
+		s: s,
+	}
+	return r, nil
+}
+
+func NewFileRepo(path string) (*repo, error) {
+	s, err := fs.NewFileStorage(path)
+	if err != nil {
+		return nil, err
+	}
+	return NewRepo(s)
+}