Improved form errors

Places some server-sent form errors inline and colors the form input borders to show their validity.
> I'm assuming es5. We haven't tried for compatibility below that in the past. I'd prefer not to if we don't have to. And if we do, it would be better to get along with es5-shim if possible. No?

Okay grand. If it's our own app running in our own global namespace I'm fine with es5-shim, but if it's a library or anything that could possibly be embedded in a user page then I won't touch the global objects. Make sense?