#515 - fix ignored sections' option triggering

This addresses #515 - it fixes the case where more than one option in an ignored section is a trigger, but only one has the correct behaviour.

The code ensures that a trigger option's section ignored state is taken into account.

The old code will not pass the new test content.

There's also a bug fix in lib/python/rose/config_editor/stack.py.

@matthewrmshin, please review.