AREImporter: fixed regression from 833056d and bugs from 31d4d4b1

iwd1 also uses IWD2ScriptName, so too much code was run, breaking
avatar removal in particular, making both iwd/how unfinishable

thanks go to merbie for bisecting
reverting 489ade973 and a few further changes

    Map::UpdateScripts: don't run scripts for actors with avatarremoval set

    true for at least bg2 and we'll use it internally in iwd2

the first concrete test case is how's starting dialog's cutscene,
which breaks with this in place, as the actor marks himself *poof*
mid-cutscene. Similar things happen in iwd2, so some other mechanic
for AF_ENABLED needs to be implemented.