Dement fix

<b>It is not a real pullrequest, cause its allready in the source on github.</b>

There was an pullrequest earlier in the year (https://github.com/Meridian59/Meridian59/commit/a27e02c829575f9cc57bac0065ddac6491011282) who lowered the durration from 5-30 minutes to 1-3 minutes (it would for real on lowest spellpower which is possible 30seconds - 3 minutes). After rewrote close to everything in dement and it seamed to work with hardcoded numbers i checked the original dement.kod again on my testserver and it workes like it should work. Im sure that the problem is the source you compiled from for the live servers and you simple forget to add the change anax made for the spell, or maybe it was not part of the last update?