Fix incorrect addressing

Address == Address1 == The first residence address

Mail == The mailing address

This might benefit from logic to say that if there's no mailing address,
use the residence address, and so on.
Further clarify Mail/Address distinction
Fill something for USCitizenYesNo field
Fill DriverLicense
Fill Relationship for household members
Re-title the PDF guide
Add a download button to housing forms

Resolves #140.
Make income editable

Fixes #143
Ask for Rails enthusiasts in civic.json
Turn off mass_assignment_sanitizer

We can start removing the deprecated attr_accessor methods now, I think.
Reduce attr_accessible in HousingForm
Add scaffold for the Employment model
Seed employments
Display employments on applicants/show
Remove unused employments_helper_test
Clean up the employments form
Don't require attr_accessible for model attibutes set by params
Fix employment redirects
Make employment addresses editable

And that fixes #146.
Fix employment submit buttons