Add exercise feedback page for pair programming study

app/views/pair_programming_exercise_feedbacks/_form.html.slim

@@ -0,0 +1,23 @@
+= form_for(@uef) do |f|
+  div
+    h1 id="exercise-headline"
+      = t('activerecord.models.user_exercise_feedback.one') + " " + @exercise.title
+  = render('shared/form_errors', object: @uef)
+  p
+    == t('pair_programming_exercise_feedback.description')
+  .mb-3
+    h5.mt-4 = t('pair_programming_exercise_feedback.difficulty')
+    = f.collection_radio_buttons :difficulty, @texts, :first, :last  do |b|
+      .form-check
+        label.form-check-label
+          = b.radio_button(class: 'form-check-input')
+          = b.text
+    h5.mt-4 = t('pair_programming_exercise_feedback.working_time')
+    = f.collection_radio_buttons :user_estimated_worktime, @times, :first, :last  do |b|
+      .form-check
+        label.form-check-label
+          = b.radio_button(class: 'form-check-input')
+          = b.text
+    = f.hidden_field(:exercise_id, :value => @exercise.id)
+    = f.hidden_field(:submission_id, :value => @submission.id)
+  .actions = render('shared/submit_button', f: f, object: @uef)

app/views/pair_programming_exercise_feedbacks/new.html.slim

@@ -0,0 +1 @@
+= render('form')