Merge pull request #3649 from phillipj/avoid-global-gulp

Use local version of gulp in build steps

.vscode/tasks.json

 {
 	"version": "0.1.0",
-	"command": "gulp",
+	"command": "./node_modules/.bin/gulp",
 	"isShellCommand": true,
 	"tasks": [
 		{

package.json

@@ -13,7 +13,8 @@
   "scripts": {
     "test": "mocha",
     "preinstall": "node build/npm/preinstall.js",
-    "postinstall": "npm --prefix extensions/vscode-api-tests/ install extensions/vscode-api-tests/ && npm --prefix extensions/json/ install extensions/json/ && npm --prefix extensions/typescript/ install extensions/typescript/"
+    "postinstall": "npm --prefix extensions/vscode-api-tests/ install extensions/vscode-api-tests/ && npm --prefix extensions/json/ install extensions/json/ && npm --prefix extensions/typescript/ install extensions/typescript/",
+    "watch": "gulp watch"
   },
   "dependencies": {
     "applicationinsights": "0.15.6",