Add upload file example

README.md

@@ -218,6 +218,32 @@ func main() {
 id: 1234; page: 1; name: manu; message: this_is_great
 ```
 
+### Another example: upload file
+
+Reference issue [#548](https://github.com/gin-gonic/gin/issues/548)
+
+```go
+func main() {
+	router := gin.Default()
+
+	router.POST("/upload", func(c *gin.Context) {
+
+	        file, header , err := c.Request.FormFile("upload")
+	        filename := header.Filename
+	        fmt.Println(header.Filename)
+	        out, err := os.Create("./tmp/"+filename+".png")
+	        if err != nil {
+	            log.Fatal(err)
+	        }
+	        defer out.Close()
+	        _, err = io.Copy(out, file)
+	        if err != nil {
+	            log.Fatal(err)
+	        }   
+	})
+	router.Run(":8080")
+}
+```
 
 #### Grouping routes
 ```go