E2E Tests & Google Drive Picker Basic Mock

- Use widget tester for tests
- GAPI picker basic mock & dummy tests for picked and cancel events
- Modify bower to point to new #3.1.1-rv version of Bootstrap
- E2E test for file pick and dialog cancel event
- Stop e2e server on gulp task error
- Angular Directive revision & E2E tests
"test" should be a dependency of "build"