Optimize gulp scripts task

- UlgifyJS is the bottle neck here.
- Don't minify vendors that already provide a minified version (go
  faster)
- Concatenate after minifying vs before (use less memory)
Separate dependencies in package.json

- Everything needed to build and run `server.js` is in "dependencies"
  (so we can use `npm install --production` in `build.sh`)
- All the rest (needed to test etc.) is in "devDependencies"
Separate config from other scripts in build
Move build step into build.sh

For Shio deployment. In "start.sh", we only rebuild "config.js" so it
takes the values of current environment variables. This will make
"start.sh" much faster.
Fix unit test
Merge pull request #30 from tidepool-org/optimize-build

Optimize build step and application start