who is visiting this content (plot and updated display edition) (#48)

* incorporate feedback

- switch to gt
- add content title and owner
- add plot
- improve layout

* renv snapshot

* adjust wording and layout slightly

* updated layout

* use v1 endpoint for hits firehose

* the default guid is the most viewed content item on the server

* Migrate to reactable, filter by selected row

* move selected user filter to earlier in pipeline

* renv snapshot

* update title layout

* simplify code

* much nicer summary and filter message

* update input method

* update date range sliders

* Add email button for each user

* improve spacing on toolbar back button

* misc improvements

* multi-select of users, use visitor credentials

* first draft of new plot

* implement new plot, improve action buttons and layout

* cleanup and bugfixes

* fix bug clearing selection state

* fix email button on connect

* layout update

* extensions machinery

* extensions machinery part 2

* Revert "extensions machinery part 2"

This reverts commit 3bbc18a.

* update extract_guid() function

Author: toph-allen

extensions/who-is-visiting-this-content/README.md

@@ -0,0 +1,3 @@
+# Content Usage Metrics Dashboard
+
+See what content is popular on your Connect instance. Dive into details for a content item to learn who's viewing it, and when.