Runtime Version Scanner: Respond to feedback from user testing (#228)

* remove complex version selector

* Update reactable data without rerendering

* Table layout and column visibility improvements

* Fix header wrapping

* Async loading of views

* add download button, fix views filter

* finalize

* tweaks

* Respond to feedback…

- Update date range inputs
- Update blank version column display
- Increase width of Last Published column

* Improve integration-add experience

* improve feeling of column width

* fix usage async and loading message

* Further increase date column width

* update manifest

Author: toph-allen