Still a blocking door in Lugdunia cave

[tchegito]

In #150 we fixed a bug about south door of "foretg", now it's about north.

Case is simple:

• you came from this map and go to the north door
• you arrive in foretg2
• you go back
• now you're blocked

Bonus: light is wrongly handled on this kind of door

[tchegito]

[Fixed in 2.54]

Adde TU for this in #149

cf09348b6975a178ed32bd70c7b8eb53fd46fe0d