Add 'R' to reload/refresh search results

I often work out of the All > Open changes screen and want to see the
latest updates quickly. To do this I currently type /, Enter to focus
the search box and re-run the query or g, o to reload the open
changes. Add R as an alias to refresh the current screen, similar to
the support already inChangeScreen2.

Change-Id: I08a9dbe4378072925090042d66d079a85fe6918f
5 files changed