Added tabs for active and completed tasks in Job page.

Moved task tables into active and completed tabs on job page.
Installed angular-ui/bootstrap project since we need the tabset directive from it.
Upgraded angular js to version 1.2.9 from 1.2.6.

Testing Done:
./gradlew run && ./gradlew build

Bugs closed: AURORA-425

Reviewed at https://reviews.apache.org/r/21825/