Format code example in README (#510)

Author: zliang-akamai

README.md

@@ -33,36 +33,35 @@ package main
 import (
 	"context"
 	"fmt"
-
-	"github.com/linode/linodego"
-	"golang.org/x/oauth2"
-
 	"log"
 	"net/http"
 	"os"
+
+	"github.com/linode/linodego"
+	"golang.org/x/oauth2"
 )
 
 func main() {
-  apiKey, ok := os.LookupEnv("LINODE_TOKEN")
-  if !ok {
-    log.Fatal("Could not find LINODE_TOKEN, please assert it is set.")
-  }
-  tokenSource := oauth2.StaticTokenSource(&oauth2.Token{AccessToken: apiKey})
-
-  oauth2Client := &http.Client{
-    Transport: &oauth2.Transport{
-      Source: tokenSource,
-    },
-  }
-
-  linodeClient := linodego.NewClient(oauth2Client)
-  linodeClient.SetDebug(true)
-  
-  res, err := linodeClient.GetInstance(context.Background(), 4090913)
-  if err != nil {
-    log.Fatal(err)
-  }
-  fmt.Printf("%v", res)
+	apiKey, ok := os.LookupEnv("LINODE_TOKEN")
+	if !ok {
+		log.Fatal("Could not find LINODE_TOKEN, please assert it is set.")
+	}
+	tokenSource := oauth2.StaticTokenSource(&oauth2.Token{AccessToken: apiKey})
+
+	oauth2Client := &http.Client{
+		Transport: &oauth2.Transport{
+			Source: tokenSource,
+		},
+	}
+
+	linodeClient := linodego.NewClient(oauth2Client)
+	linodeClient.SetDebug(true)
+
+	res, err := linodeClient.GetInstance(context.Background(), 4090913)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("%v", res)
 }
 ```