Generate docs as READMEs for examples

Signed-off-by: jolheiser <john.olheiser@gmail.com>

examples/flagset/main.go

@@ -28,7 +28,7 @@ func main() {
 		panic(err)
 	}
 
-	write("flagset.md", md)
+	write("README.md", md)
 }
 
 func write(path, content string) {

examples/multiple/main.go

@@ -66,7 +66,7 @@ func main() {
 	if err != nil {
 		panic(err)
 	}
-	write("command-sub.md", md)
+	write("README.md", md)
 }
 
 func write(path, content string) {

examples/single/main.go

@@ -35,7 +35,7 @@ func main() {
 	if err != nil {
 		panic(err)
 	}
-	write("single.md", md)
+	write("README.md", md)
 }
 
 func write(path, content string) {