Add comments.  Code clean.
Fix but of undefined author.id.  Switched to curUser.provider, correct property.
Add promise handling to addReview
Create utility service for common funtions and to maintain a single location for things like firebase url.
Add firebase url as part of utitlity service. Add push to addReview.
Add review to spot working, but digest bug.
Add safeApply function to utility belt.