[hde_mod] Add more SoD features

[potmdehex]

HD Edition lacks SoD features such as re-visiting object with space bar, moats doing damage etc. HDE Mod already adds space bar re-visit and it would be good to add more features (a list can be made and added here).

Ideally all SoD features _and _ content (monsters, artifacts, other objects, Conflux town, campaigns) would eventually be supported, but it would be very time consuming to implement it all. A good starting point would be some mechanics such as moat damage.

Done definition (rough, to be improved):
SoD features added