started implementing teams

db/migrate/20150128083123_create_teams.rb

@@ -0,0 +1,8 @@
+class CreateTeams < ActiveRecord::Migration
+  def change
+    create_table :teams do |t|
+      t.string :name
+      t.timestamps
+    end
+  end
+end

db/migrate/20150128084834_create_internal_users_teams.rb

@@ -0,0 +1,8 @@
+class CreateInternalUsersTeams < ActiveRecord::Migration
+  def change
+    create_table :internal_users_teams do |t|
+      t.belongs_to :internal_user, index: true
+      t.belongs_to :team, index: true
+    end
+  end
+end

db/migrate/20150128093003_add_team_id_to_exercises.rb

@@ -0,0 +1,5 @@
+class AddTeamIdToExercises < ActiveRecord::Migration
+  def change
+    add_reference :exercises, :team
+  end
+end