Fix off-by-one error in favor_modifier.

This was corrected earlier, but I didn't get it quite right that time.
There were instances when IfUnlessModifier reported a violation, but
fixing the violation would make the line too long.

Conflicts:
	CHANGELOG.md
Merge pull request #241 from jonas054/fix_favor_modifier_again

Fix off-by-one error in favor_modifier.