add static global function & add seocms example

@@ -38,4 +38,5 @@ beego is licensed under the Apache Licence, Version 2.0
 ## Use case
 
 - Displaying API documentation: [gowalker](https://github.com/Unknwon/gowalker)
+- seocms: [seocms](https://github.com/chinakr/seocms)
 - CMS: [toropress](https://github.com/insionng/toropress)

@@ -182,6 +182,11 @@ func SetStaticPath(url string, path string) *App {
 	return BeeApp
 }
 
+func DelStaticPath(url string) *App {
+	delete(StaticDir, url)
+	return BeeApp
+}
+
 func Filter(filter http.HandlerFunc) *App {
 	BeeApp.Filter(filter)
 	return BeeApp