Create User and Friendship Model

• railscasts.com/episodes/163-self-referential-association

• stackoverflow.com/questions/5612736/how-to-implement-a-friendship-model-in-rails-3-for-a-social-networking-applicati

Use OmniAuth for authentication using username/password or Facebook/Google/Whatever

• github.com/intridea/omniauth

• github.com/mkdynamic/omniauth-facebook

Contain trailmarkers within trails