Support surfacing non-fatal errors more aggressively in test builds

[nbrooke]

Right now crash / error reporting is either turned off in test builds (if we are using something more invasive like BugSee) or just report normally (which might not be supper useful if interesting new errors are just appearing in the general set from production). There are some things we can do to improve the current situation (#72, #83), but there are also other things we could do to make non-fatals in that environment MORE obvious.

For example showing an onscreen popup of some kind any time a non-fatal happens, with an immediate option to send detailed logs, maybe trigger a BugSee event if it's active, etc.

This would make it more likely to catch serious problems that don't cause visible bugs when they happen immediately, and up our chances of getting more useful error reports from internal or client QA.