docs: add web scraper example

Author: CoolSpring8

.gitattributes

@@ -1 +1,2 @@
 build/* linguist-vendored
+examples/web-scraper/index.html linguist-vendored

examples/defer-scripts/main.go

@@ -1,10 +1,12 @@
+// Usage: curl -NL https://git.io/JeOSZ | go run main.go
 package main
 
 import (
-	"github.com/coolspring8/go-lolhtml"
 	"io"
 	"log"
 	"os"
+
+	"github.com/coolspring8/go-lolhtml"
 )
 
 func main() {

examples/mixed-content-rewriter/main.go

@@ -1,11 +1,13 @@
+// Usage: curl -NL https://git.io/JeOSZ | go run main.go
 package main
 
 import (
-	"github.com/coolspring8/go-lolhtml"
 	"io"
 	"log"
 	"os"
 	"strings"
+
+	"github.com/coolspring8/go-lolhtml"
 )
 
 func main() {