highlight all uses of a link when it is selected
Remove some debugging console.logs.
Fix tests to return tuples as ref payloads from htmlifiers.
Merge same-symbol-highlighting while showing context menu. Close #178.
Change "v-root" to "vagrant-root" in Vagrant file.

This clears warnings like in https://ci.mozilla.org/job/dxr/172/console: "The 'v-root' shared folders have been renamed to 'vagrant-root'. Assuming you meant 'vagrant-root'..."