Enable use of override for session timeout in hours, fix captcha bypass bug. (#51)

* - Enable use of override for session timeout. This is more useful than having to hard-code and rebuild the code for the previous 4 hour limit. Just set environmental variable and start the app.
- Future work may involve breaking down into minutes, but this is a good minimum delivery to provide value to end-user/developer.

- Fixes bug in Captcha code by introducing new landing page. This is not a new go template, it's a separate HTML file because SRP - single reponsibility principle. Happy for this to be refacted after merging commit.

- Fix for including Docker 1.12 override has been removed for later PR.

* Merge

* Reinstate 'material' JS include'

* https for JS includes

* HTTPs for JS in bypass

api.go

@@ -5,28 +5,24 @@ import (
 	"net/http"
 	"os"
 
+	"flag"
+	"strconv"
+
 	"github.com/franela/play-with-docker/handlers"
 	"github.com/franela/play-with-docker/services"
 	"github.com/franela/play-with-docker/templates"
 	"github.com/gorilla/mux"
 	"github.com/urfave/negroni"
-	"flag"
-	"strconv"
 )
 
 func main() {
-
 	var portNumber int
 	flag.IntVar(&portNumber, "port", 3000, "Give a TCP port to run the application")
 	flag.Parse()
 
-	welcome, tmplErr := templates.GetWelcomeTemplate()
-	if tmplErr != nil {
-		log.Fatal(tmplErr)
-	}
+	bypassCaptcha := len(os.Getenv("GOOGLE_RECAPTCHA_DISABLED")) > 0
 
 	server := services.CreateWSServer()
-
 	server.On("connection", handlers.WS)
 	server.On("error", handlers.WSError)
 
@@ -45,9 +41,19 @@ func main() {
 	r.StrictSlash(false)
 
 	r.HandleFunc("/ping", http.HandlerFunc(handlers.Ping)).Methods("GET")
+
 	r.HandleFunc("/", http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
-		rw.Write(welcome)
+		if bypassCaptcha {
+			http.ServeFile(rw, r, "./www/bypass.html")
+		} else {
+			welcome, tmplErr := templates.GetWelcomeTemplate()
+			if tmplErr != nil {
+				log.Fatal(tmplErr)
+			}
+			rw.Write(welcome)
+		}
 	})).Methods("GET")
+
 	r.HandleFunc("/", http.HandlerFunc(handlers.NewSession)).Methods("POST")
 
 	r.HandleFunc("/sessions/{sessionId}", http.HandlerFunc(handlers.GetSession)).Methods("GET")
@@ -57,6 +63,7 @@ func main() {
 	h := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		http.ServeFile(w, r, "./www/index.html")
 	})
+
 	r.HandleFunc("/p/{sessionId}", h).Methods("GET")
 	r.PathPrefix("/assets").Handler(http.FileServer(http.Dir("./www")))
 	r.HandleFunc("/robots.txt", http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
@@ -68,7 +75,7 @@ func main() {
 	n := negroni.Classic()
 	n.UseHandler(r)
 
-	log.Println("Listening on port "+ strconv.Itoa(portNumber))
+	log.Println("Listening on port " + strconv.Itoa(portNumber))
 	log.Fatal(http.ListenAndServe("0.0.0.0:"+strconv.Itoa(portNumber), n))
 
 }