Remember and display recent jobs locally

Currently the jobs page displays a list of recent jobs by querying the backend JobOperator. If the backend server was just started, this list is empty. Or some job names may be evicted from memory after some idle time.

We should be able to locally remember recent job names via local storage to supplement the list of recent jobs.

There is a https://github.com/grevory/angular-local-storage, for managing local storage in AngularJS-based app, including fallback to cookies. But our use of local storage is relatively simple, so doesn't warrant an extra module.