Document undocumented names

[jpthiele]

The check currently lists 78 Elements with undocumented names.

[j-fu]

See #40 :)

[j-fu]

Fixing is a lot of work, may be @chmerdon can use some help with this. My be Liam or Fedor?

[j-fu]

Also see JuliaTesting/Aqua.jl#313