Adds email field to user

Adds email field to user as well as a new constructor, getter, and setter for the email field.

Author: nfbrown, ellychou, mtnguyenwpi
Merge branch 'team9dev' into feature-useremail
Changes admin page to work with user email

Updates admin page to show field for setting email for user. Also updates UserSerializer and UserDeserializer.

Authors: nfbrown, ellychou, mtnguyenwpi
Adds a user preferences panel

Right now just contains notification settings, but might be changed with
future requirements
Adds tests for User email field

Authors: nfbrown, ellychou, mtnguyenwpi
Merge pull request #19 from dbeckwith/feature-useremail

Feature useremail
Merge branch 'team9dev' into viewEstimates