Change expressions used in directives

* It is highly recommended to use expressions for objects rather than
  primitives in directives. See
  https://github.com/angular/angular.js/wiki/Understanding-Scopes.
Use angular-ui/bootstrap

* bower.json was updated.
* JS file was included in index.html and Karma configuration.
* AngularJS module dependency was updated.
Rename some test spec groups [ci skip]
Fix the option for Grunt task `watch`

* `connect:test` task was added to `tasks` entry for `watch:jsTestE2E`
  so that E2E tests run correctly on changes of E2E test files when
  Grunt task `watch` is running.
Refactor E2E test specs for main screen [ci skip]

* Someday 'page objects' pattern will be introduced.