Event handler errors are silently swallowed

[kriszyp]

The return statement inside the finally block in the emit causes thrown errors to be caught and silently ignored:
https://github.com/SitePen/dstore/blob/1.x/Store.js#L141

Ideally it would be nice if we were not catching errors at all, to avoid interrupting the error stack, but at the very least if we are going to be catching errors, we should at least report them with some console output so they don't just silently disappear.

[xmedeko]

Very annoying bug, it's very hard to hunt bugs - swallowed errors.