ci(travis): Updated generated travis.yml

- It wasn't compiling right away (got rid of bower)
- Also the tooling was needed from node-gyp
- And some caching between builds

templates/app/.travis.yml

@@ -1,12 +1,22 @@
 language: node_js
 node_js:
-  - 4.4.6
+  - 6
 matrix:
   fast_finish: true
   allow_failures:
     - node_js: 5.12.0
 before_script:
-  - npm install -g gulp-cli<% if (filters.sass) { %>
+  - npm install -g gulp-cli node-gyp<% if (filters.sass) { %>
   - gem install sass<% } %>
-  - bower install
 services: mongodb
+cache:
+  directories:
+    - node_modules
+env:
+  - CXX=g++-4.8
+addons:
+  apt:
+    sources:
+    - ubuntu-toolchain-r-test
+    packages:
+    - g++-4.8