Improve Angular admin grids with friendlier linked object display

[Mike Rylander]

The new Angular grid component, as used in the admin interfaces, shows linked objects with a has_a relationship to the main type as the pkey value of the linked objects. When there is a selector set for the linked object type, we can do better by showing the value from the selector field. Branch forthcoming to make it so...

[Mike Rylander (mrylander)]

And here it is:

https://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/miker/lp-1819179-admin-grid-has_a-flesh

Thanks, Bill, for carrying it over the goal line!

[Bill Erickson (berick)]

Follow up branch which merges the code from bug #1812670 into this branch and adds some additional logic to the auto-fleshing layers to handle "map"-ed fields.

https://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/berick/lp1819179-and-1812670-pcrud-etc-flesh

Going to mark bug #1812670 as a duplicate of this one since they cover the same ground.

[Dan Wells (dbw2)]

Does the job as described; pushed to master. Thanks, Mike and Bill!

Even though it isn't targeted, I tried to backport to rel_3_2, but it had conflicts. Any opinions on the necessity of that backport from others?

[Mike Rylander (mrylander)]

Follow-up for Dan Wells: I don't think it's important for 3.2, as there's no Angular7 exposed for Official(tm) production use.