Prop variation for recurring same actor file is needed

[sanderd17]

For fields, it would be nice if the actor present on it could variate randomly. But there are several problems for this.

First of all the for loop around line 520 in ObjectBase.cpp checks if some variation for that actor has been chosen before. Of course, this loop should be removed to have randomness, or adapted to work with links with the prop point name (as explained later).

But a bigger problem is explained around line 560. Namely that only the variation name is remembered. So if you have 20 times bush a, b or c. It's quite certain the list will always contain a, b and c, and as a result, the same variation will always be chosen. A better way to store it would be something linked. A simple concatenation of the prop point name and the variation would work, but it would be better to have a proper link.

It's also possible that the seed should be changed to not get the same results every time.