LP#1813788: add example of grid improvements to sandbox

LP#1813788: add example of grid improvements to sandbox

This patch adds a new grid to the Angular sandbox page
that demonstrates the following features introduced
in the previous patch:

- grid filtering
- stick grid headers
- grid reloads without losing one's current paging
  location

Sponsored-by: MassLNC
Sponsored-by: Georgia Public Library Service
Sponsored-by: Indiana State Library
Sponsored-by: CW MARS
Sponsored-by: King County Library System
Signed-off-by: Galen Charlton <gmc@equinoxinitiative.org>