Add initial Evaluation model and new form
Fix evaluation model bugs

- Advisors can now successfully create and view evaluations
Add application and db uniqueness validations

- Add multicolumn uniqueness validations
Add evaluation index view; miscellaneous changes
Move Mailer actions to model callbacks

- Move ActionMailer actions from controller actions to callbacks of
  their respective models
Add delegations and flash messages

- Refactors and cleans up several methods
Refactors ability.rb, updates /vendor/cache
Refactor Evaluation model

- Evaluation now belongs_to submission, and submission has_one
  evaluation
Add Quarter model

- Make association between Quarter and Project