Change GitHub pages deploy strategy

Author: domenic

.gitignore

@@ -3,6 +3,10 @@ node_modules/
 npm-debug.log
 package-lock.json
 
+# deploy keys
+deploy_key
+deploy_key.pub
+
 # project specific
 coverage/
 test/web-platform-tests/

.travis.yml

@@ -1,5 +1,9 @@
 sudo: false
 
+branches:
+  only:
+  - master
+
 language: node_js
 node_js: stable
 
@@ -13,10 +17,17 @@ script:
 before_deploy:
   - bash scripts/deploy-live-viewer.sh
 
+before_deploy:
+- openssl aes-256-cbc -K $encrypted_3767330e5762_key -iv $encrypted_3767330e5762_iv -in deploy_key.enc -out deploy_key -d
+
 deploy:
   provider: pages
-  local-dir: out
-  committer-from-gh: true
-  skip-cleanup: true
-  keep-history: true
-  github-token: $GH_TOKEN
+  local_dir: out
+  deploy_key: deploy_key
+  edge:
+    branch: master
+
+notifications:
+  email:
+    on_success: never
+    on_failure: always