Email i18n improvements

- Separate email keys from UI keys to fix unit tests
- Updated tests to work with latest files
Should we just hash `'<%= target %>/optimized/shared/oae/bundles`?

Pro: Any bundle directory we put underneath automatically gets hashed
Con: The hash changes more frequently

I don't mind if it stays the same just thought I'd ask. Bonus points if `'<%= target %>/optimized/shared/oae/bundles/*` actually works.. it might.