#586 fix npm scripts for demo app and demo projects

- pre-build TypeScript code before running watchers
- don’t clean (rimraf) destination folders on watcher (done on
pre-build, fixes many browser load errors)
- simplified ‘tslint’ tasks for demo projects
- running ’tsc’ and ‘tsc -w’ from local node_modules (don’t expect
global typescript compiler)

demo-shell-ng2/package.json

@@ -6,7 +6,8 @@
   "scripts": {
     "postinstall": "typings install",
     "clean": "rimraf node_modules typings",
-    "start": "npm run tslint && concurrently \"npm run tsc:w\" \"license-check\"  \"npm run serve\" ",
+    "build": "npm run tslint && npm run tsc && npm run licensecheck",
+    "start": "npm run build && concurrently \"npm run tsc:w\" \"npm run serve\" ",
     "aws": "node app.js",
     "tsc": "tsc",
     "tsc:w": "tsc -w",