build(npm): upgrade to npm v3

Closes angular#3193

Author: btford

.travis.yml

@@ -60,6 +60,7 @@ addons:
   firefox: "38.0"
 
 before_install:
+- npm install -g npm@3.5.2
 - node tools/analytics/build-analytics start ci job
 - node tools/analytics/build-analytics start ci before_install
 - echo ${TSDRC} > .tsdrc
@@ -77,7 +78,9 @@ install:
   # Check the size of caches
   - du -sh ./node_modules || true
   # Install npm dependecies
-  - npm install
+  # check-node-modules will exit(1) if we don't need to install
+  # we need to manually kick off the postinstall script if check-node-modules exit(0)s
+  - node tools/npm/check-node-modules --purge && npm install || npm run postinstall
   - node tools/analytics/build-analytics success ci install
 
 before_script:

gulpfile.js

@@ -3,7 +3,7 @@
 // THIS CHECK SHOULD BE THE FIRST THING IN THIS FILE
 // This is to ensure that we catch env issues before we error while requiring other dependencies.
 require('./tools/check-environment')(
-    {requiredNpmVersion: '>=2.14.7 <3.0.0', requiredNodeVersion: '>=4.2.1 <5.0.0'});
+    {requiredNpmVersion: '>=3.5.2 <4.0.0', requiredNodeVersion: '>=4.2.1 <5.0.0'});
 
 
 var del = require('del');
@@ -327,7 +327,9 @@ gulp.task('lint', ['build.tools'], function() {
       "requireParameterType": true,
       "requireReturnType": true,
       "semicolon": true,
-      "variable-name": [true, "ban-keywords"]
+
+      // TODO: find a way to just screen for reserved names
+      "variable-name": false
     }
   };
   return gulp.src(['modules/angular2/src/**/*.ts', '!modules/angular2/src/testing/**'])