added intervention controller and stuff

app/models/intervention.rb

@@ -1,15 +1,16 @@
 class Intervention < ActiveRecord::Base
 
-  NAME = %w(overallSlower longSession syntaxErrors videoNotWatched)
-
   has_many :user_exercise_interventions
   has_many :users, through: :user_exercise_interventions, source_type: "ExternalUser"
-  #belongs_to :user, polymorphic: true
-  #belongs_to :external_users, source: :user, source_type: ExternalUser
-  #belongs_to :internal_users, source: :user, source_type: InternalUser, through: :user_interventions
- # alias_method :users, :external_users
-  #has_many :exercises, through: :user_interventions
 
-  validates :name, inclusion: {in: NAME}
+  def to_s
+    name
+  end
+
+  def self.createDefaultInterventions
+    %w(BreakIntervention QuestionIntervention).each do |name|
+      Intervention.find_or_create_by(name: name)
+    end
+  end
 
 end