edit: Rename some of helpers, and reorder parameters

edit: Rename some of helpers, and reorder parameters

doland() edits a sector, not a land unit.  That one's called dounit().
Lacks taste.  Call the helper for editing a FOO edit_FOO(), and make
the FOO * the first parameter instead of the last.

Rename the print helpers to print_FOO(), for consistency.  Also frees
up identifier prnat for the next commit.

While there, clean up an unused #define.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>