Dual ISO auto expo: remove redundant menu option, and some old comments.
Created originally on Bitbucket by Audionut
Was already merged in Bitbucket before import, marked as merged by the import user
Source changeset not longer availableat the time of import. Commit listwill look empty
Since you can adjust the min DR gained, AUTO_EXPO_TRIGGER_MINUS_2EV is redundant.
Add +2.5 EV to min DR gained. A little extra adjustment, in case I missed something specific about the removed trigger mode. Also, useful if you don't want dual ISO, until the DR is extremely large.
Remove some redundant comments.