[Therion] Nesting surveys

[Stacho Mudrak]

Quoting Andrew Atkinson <andrew at wotcc.org.uk>:

> The aim is so I can run each section of cave (represented by a directory)
> individually or the whole thing from the root, without editing the whole
> cave.
>
> Hope this helps you understand what I am trying to do.

Yes. I think, now I understand your problem. I am not sure, but simple solution 
 of this problem would be not to generate errors, if one station is imported
twice - from global .3d and from local .3d file. And of course allways prefer
the coordinates from the global file. This will probably work, I am just able
to start working on it after Christmas :)

> For information: Everyone who surveyed drew up there own surveys and
> Therionised them, even computer phobic's became quite enthusiastic. On the
> last day of the trip the plans where printed and handed to the local park
> warden. Okay, they where not perfect. This would not have been possible
> without Therion, so thanks.

This is great!

S.