Add problem count changing to the admin dashboard

app/controllers/admin/dashboard_controller.rb

@@ -1,4 +1,16 @@
 class Admin::DashboardController < AdminController
   def index
+    @current_problem_count = Problem.count
+  end
+
+  def update_problem_count
+    begin
+      new_problem_count = params[:problem_count].to_i
+      raise t('no_problem_count') unless new_problem_count
+      Problem.update_count(new_problem_count)
+      redirect_to({:controller => 'admin/dashboard', :action => :index}, notice: t('.success_message'))
+    rescue => e
+      redirect_to({:controller => 'admin/dashboard', :action => :index}, alert: t('.failure_message', error: e.message))
+    end
   end
 end