Add problem pagination with will_paginate. Fix #2

app/controllers/problems_controller.rb

@@ -4,7 +4,7 @@ class ProblemsController < ApplicationController
   # GET /problems
   # GET /problems.json
   def index
-    @problems = Problem.all
+    @problems = Problem.paginate(page: params[:page])
   end
 
   # GET /problems/1

app/models/problem.rb

@@ -1,4 +1,6 @@
 class Problem < ActiveRecord::Base
   validates :title, :content, presence: true
   validates :title, uniqueness: true
+
+  self.per_page = 50
 end

app/views/problems/_problem_pagination.html.erb

@@ -0,0 +1 @@
+<%= will_paginate @problems, renderer: BootstrapPagination::Rails %>

app/views/problems/index.html.erb

@@ -1,5 +1,6 @@
 <h1>Listing problems</h1>
 
+<%= render 'problem_pagination' %>
 <table class="table table-striped table-bordered">
   <thead>
     <tr>
@@ -17,7 +18,7 @@
     <% end %>
   </tbody>
 </table>
-
+<%= render 'problem_pagination' %>
 <br>
 
 <%= link_to 'New Problem', new_problem_path, class: 'btn btn-default' %>