Enhanced warnings for overlapping rule definitions

[GoogleCodeExporter]

In as much detail as possible, please describe what you would like to see.

If two rules cover similar domains of answers, there should be a warning 
notifying the creator of this. For instance, if one answer group has a rule 
that says "is greater than 3" and another says "is greater than 5". These may 
or may not behave as the creator expects, since they are overlapping in 
possible answers.

A more serious case for this issue would be:

-One answer group with a rule "if answer equals 'Hello'"
-Another group with a rule "if answer contains ''"
-Another group with a rule "if answer equals 'Kitten'"

Contains and empty string for a text input interaction automatically takes all 
answers. In this case, since "equals 'Hello'" is before the contains rule, then 
only inputs of Hello will receive correct feedback. If the user enters 
'Kitten', however, it will use the feedback for the second group since the 
"contains ''" will have the best classification for that answer.

Instead, there should be a warning saying that these different circumstances 
have overlapping rules and that the creator should try and make the rules more 
explicit. It would also be nice to have suggestions for this, as well (possibly 
part of Issue 860 for suggestions).

Original issue reported on code.google.com by [email protected] on 15 Jul 2015 at 1:22