sandbox: update nacl runtime and deploy instructions

Fixes golang/go#5096.

Change-Id: I21ca0c7c9798439f68ce0616e9d493b5536f1833
Reviewed-on: https://go-review.googlesource.com/19785
Reviewed-by: Chris Broadfoot <cbro@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>

README

diff --git a/README b/README
index 2f02bee..fb6426b 100644
--- a/README
+++ b/README
@@ -4,4 +4,11 @@
 
 To deploy a new sandbox server, use the gcloud tool:
 
-$ gcloud --project golang-org preview app deploy --set-default sandbox/app.yaml
+$ gcloud --project golang-org preview app deploy --no-promote sandbox/app.yaml
+
+Use the Cloud Console's to set the new version as the default:
+	https://cloud.google.com/console/appengine/versions?project=golang-org&moduleId=sandbox
+Then test that play.golang.org and tour.golang.org are working before deleting
+the old version.
+
+

sandbox/Dockerfile

diff --git a/sandbox/Dockerfile b/sandbox/Dockerfile
index 4cabc3d..4fc39c5 100644
--- a/sandbox/Dockerfile
+++ b/sandbox/Dockerfile
@@ -4,8 +4,9 @@
 
 FROM golang:1.6
 
+RUN apt-get update && apt-get install -yq --no-install-recommends patch bzip2
+
 # enable faketime
-RUN apt-get update && apt-get install -yq --no-install-recommends patch
 ADD enable-fake-time.patch /usr/local/go/
 RUN patch /usr/local/go/src/runtime/rt0_nacl_amd64p32.s /usr/local/go/enable-fake-time.patch
 
@@ -20,7 +21,7 @@
 
 # Build the Go nacl tool chain.
 RUN cd /usr/local/go/src && GOOS=nacl GOARCH=amd64p32 ./make.bash --no-clean
-RUN cd /usr/local/bin && curl -s -O https://storage.googleapis.com/gobuilder/sel_ldr_x86_64 && chmod 0755 sel_ldr_x86_64
+RUN curl -s https://storage.googleapis.com/nativeclient-mirror/nacl/nacl_sdk/44.0.2403.157/naclsdk_linux.tar.bz2 | tar -xj -C /usr/local/bin --strip-components=2 pepper_44/tools/sel_ldr_x86_64
 
 # add and compile tour packages
 RUN GOOS=nacl GOARCH=amd64p32 go get \