support bind uri param (#1612)

* support bind uri (1)

* uri binding successful run

* fix vet warning: github.com/gin-gonic/gin/internal.Param composite literal uses unkeyed fields

* fix code style

* update function name

* fix test function signature

* add test for CanSet

* update readme and add test case

* remove internal.Params

* add coverage

* fix warning

README.md

@@ -39,6 +39,7 @@ Gin is a web framework written in Go (Golang). It features a martini-like API wi
     - [Custom Validators](#custom-validators)
     - [Only Bind Query String](#only-bind-query-string)
     - [Bind Query String or Post Data](#bind-query-string-or-post-data)
+    - [Bind Uri](#bind-uri)
     - [Bind HTML checkboxes](#bind-html-checkboxes)
     - [Multipart/Urlencoded binding](#multiparturlencoded-binding)
     - [XML, JSON, YAML and ProtoBuf rendering](#xml-json-yaml-and-protobuf-rendering)
@@ -793,6 +794,40 @@ Test it with:
 $ curl -X GET "localhost:8085/testing?name=appleboy&address=xyz&birthday=1992-03-15"
 ```
 
+### Bind Uri
+
+See the [detail information](https://github.com/gin-gonic/gin/issues/846).
+
+```go
+package main
+
+import "github.com/gin-gonic/gin"
+
+type Person struct {
+	ID string `uri:"id" binding:"required,uuid"`
+	Name string `uri:"name" binding:"required"`
+}
+
+func main() {
+	route := gin.Default()
+	route.GET("/:name/:id", func(c *gin.Context) {
+		var person Person
+		if err := c.ShouldBindUri(&person); err != nil {
+			c.JSON(400, gin.H{"msg": err})
+			return
+		}
+		c.JSON(200, gin.H{"name": person.Name, "uuid": person.ID})
+	})
+	route.Run(":8088")
+}
+```
+
+Test it with:
+```sh
+$ curl -v localhost:8088/thinkerou/987fbc97-4bed-5078-9f07-9141ba07c9f3
+$ curl -v localhost:8088/thinkerou/not-uuid
+```
+
 ### Bind HTML checkboxes
 
 See the [detail information](https://github.com/gin-gonic/gin/issues/129#issuecomment-124260092)