[2] Prevent additional state properties on Profile page from being POSTed

[MitchellDill]

Currently, the updateAccountData is being invoked on the profile page with the profile page's entire state object, which includes some page-specific stuff we don't wanna send to the database (passwordIsHidden, etc). We'll just want to make sure we only send the user object to the database!

This will likely intersect somewhat with #165 --Brandon is working to reorganize the POST/setState flow at app level, so that'll probably be relevant.

Bugfix Outline

1. Refactor profile page info updates to ensure only the updated user object to the app level for state update/POSTing
2. Check DB to ensure no additional fields have been added to the user's document
3. Ensure that when returning the profile page, all the fields you've udpdated are still updated