feat: add synology NAS in oss (#16)

synology/README.md

@@ -0,0 +1,36 @@
+# Synology
+
+[Synology](https://www.synology.com) backend for [QOR OSS](https://github.com/qor/oss)
+
+## Usage
+
+```go
+import "github.com/qor/oss/synology"
+
+func main() {
+  storage := synology.New(&synology.Config{
+    AccessID:  "access_id",
+    AccessKey: "access_key",
+    Endpoint:  "your endpoint",
+  })
+
+  // Save a reader interface into storage
+  storage.Put("/sample.txt", reader)
+
+  // Get file with path
+  storage.Get("/sample.txt")
+
+  // Get object as io.ReadCloser
+  storage.GetStream("/sample.txt")
+
+  // Delete file with path
+  storage.Delete("/sample.txt")
+
+  // List all objects under path
+  storage.List("/")
+
+  // Get Public Accessible URL (useful if current file saved privately)
+  storage.GetURL("/sample.txt")
+}
+```
+