I am not happy with the localization interface for admins, but it is the
easier that i could think of (for me, i guess), with a separate for
each language.
I am not at all proud of the use of RecordArray, but i did not see the
need to create and register a type just to show the translation links.
I might change my mind when i need to add more and more translation
links, but only it the current interface remains, which i am not that
sure at the moment.
For now, there is only the label, type, and active fields. We will need
some field to hold the area on the map, but this requires #4, and
possibly #6, to be finished.
Part of #27.
Had to export and move PublicPage struct to template because i can not
import app from campsites/types: app already imports campsite for the
http handler, and it, in turn, imports the types package for its own
http handler; an import loop.
Also had to replace PublicPage.MustRender with a Setup function because
the page passed down to html/template was the PublicPage struct, not
whatever struct embeds it. I was thinking more of Java inheritance here
rather than struct embedding.