Support nested works

[mjgiarlo]

Descriptive summary

This is an epic ticket wrapping up all tickets related to created arbitrarily nested works in Sufia. Please link other tickets related to this feature below.

• Add work to another work (in_works) #1709
• UI Create _find_work_widget partial #1563
• Add contained works (members) #1710
• Work show page -- re-label text if no relationships exist #1861
• Batch Create New Works – Display of Works #1970
• Verify contextual nested works don't break the UI #2111
• Remove/rework view overrides to support contextual nested works from CC  #2197
• Enables Works within Works and related UI and functionality #2243

[mjgiarlo]

@eliotjordan is interested in this work and how it might connect to existing work in GeoConcerns.

@tpendragon has done some related work in Plum that IIRC will be extracted to CurationConcerns. (We should link that in here once it's ready.)

@vantuyls ping.

[vantuyls]

pinging @zhang4952, @revgum, @straleyb, @luisgreg99, @wickr, @mickeroo

[mjgiarlo]

Closing this epic.