Remove references to BASE_DOMAIN

It’s no longer used.
Add comcast.net to list of generic_domains
Update contribution guidelines.
Remove unused specs and references to old admin.
Localize validation error messages.
Make authentication email addresses customizable
Add spec for custom confirmation mailer address

Also set default value in config/settings.yml.
Add a note about settings.yml use in pull requests
Add note about not committing settings.yml in PRs.
Added text for the negative state of a TTY number

Previously, when adding a phone number, you had the choice of setting
the phone type to a blank line or "TTY". We have clarified this by
changing the choices to "Not a TTY number" or "TTY number". The values
set are the same as previously.
Added advice to the extension field on phone numbers
Added visual indicators between repeated form objects

Issue #193 discussed one specific place that the admin interface needed
a visual indicator between buttons. That same pattern repeats itself
throughout the location form, so this commit addresses all of them. In
addition, it gives a visual indicator between each element in a list of
children.
Merge branch 'authentication_emails' of https://github.com/kjperry/ohana-api into kjperry-authentication_emails
Merge branch 'kjperry-authentication_emails'
Clean up formatting in settings.yml
Remove required attribute until we find workaround

See issue #207 for desired solution.
Closes #200.
Merge pull request #208 from codeforamerica/200-remove-required-attribute

Remove required attribute until we find workaround
Merge pull request #205 from cndreisbach/issue-195

Added advice to the extension field on phone numbers
Fixed specs to match new TTY text
Moved visual indicators so they appear on new elements

The lines between repeated sub-forms (contacts, phone numbers, and the
like) were not appearing on new sub-forms added dynamically. This fixes
that. In addition, this fixes all tests that were broken by the button
text change from "Add a(n) X" to "Add a new X"