Wonder foundation size smaller than footprint

[elexis]

When trying to select the briton wonder foundation, one has to click somewhere on the middle of it instead of anywhere on the footprint.

[Stan]

In 20836:

Fixes #4634
Update Theatron and Stonehenge foundations making them with more props
Make Stonehenge foundation slightly bigger allowing one to select it without having to place the cursor in the middle.

[elexis]

Thanks, that was annoying :-)