PulpV2 - Updating TODOs found in UserMailer to use default organization
for the user instead of the just the first organization.
PulpV2 - Adds missing User model tests and cleans up user.rb.
PulpV2 - Removing spec tests that are no longer valid with new
test setup.
PulpV2 - Simplifies a join to reduce the number of DB calls.
Merge pull request #1409 from ehelms/pulpv2

Pulpv2 - User model tests, user model file clean-up.