Raise Volcano Fix

[FrancoK]

The spell in MoM 1.0 manual says:
Raises a volcano, destroying all food and minerals provided by a
target map square (only map squares that do not already have hills,
mountains or nodes may be targets for this spell). Such volcanoes
permanently provide mana (one per turn) to the casting wizard. If
this spell is cast on a city, each building within the city has a 15%
probability of being destroyed. Newly raised volcanoes also have an
enhanced chance of containing special mineral deposits.

The 1.31 patch came with this brief sentence:
"Volcanoes have a 2% chance to revert to mountains each turn (with a 5% chance of providing a mineral vein)."

MoM Version	Mana provided	Revert to mountain	New vein	Damage to city
1.0	1 permanent	Not implemented	20%	15%
1.31	1 until revert	2%/turn	5%	15%

Brief technical review

Seravy found, as Asfex did before, the code to activate the new mineral vein, when the volcano is created:
The code is not working (immediately after checking for an eventual new vein, all the specials on the tile are erased).

By swapping the order of the events (clear tile before and check if there is a new vein later) the spell will work and create with a 20% chance a new vein when the volcano is created.

Checking and creating the new vein when the volcano reverts to mountain is more complex.

What do you think we should do with this bug?
Leave the bug as is. (can be done now)
Activate at the volcano creation the 20% chance for a new vein. (can be done now)
Activate at the volcano creation the 5% chance for a new vein. (can be done now)
Activate at the volcano revert the 5% chance for a new vein. (need to find the fix)
Activate at the volcano creation the 20% chance for a new vein and a 5% at revert. (need to find the fix)