title: Django like button dosen't increment and redirect me to the same page
body: <p>I have a problem with like button it doesn't work at all. In the template I use 
  <code>{{ post.likes }}</code> to show likes count  and for the button I use <code>&lt;a href="{% url 'post_like' pk=post.pk %}" class="btn btn-block hvr-bounce-in"&gt;</code></p>
  
  <p>This is views.py</p>
  
  <pre><code>from django.http.response import HttpResponse, HttpResponseRedirect
  from django.shortcuts import render, get_object_or_404, redirect, render_to_response
  from django.template import Context
  from django.utils import timezone
  from django.views.generic import View
  
  from blog.forms import CommentForm, PostForm, SearchForm
  from blog.models import Post
  
  
  def post_list(request):
      posts = Post.objects.filter(published_date__lte=timezone.now()).order_by('published_date')[0:50]
      return render(request, 'blog/index.html', {'posts': posts})
  
  
  def post_detail(request, pk):
      post = get_object_or_404(Post, pk=pk)
      return render(request, 'blog/post_detail.html', {'post': post})
  
  
  def add_comment_to_post(request, pk):
      post = get_object_or_404(Post, pk=pk)
      if request.method == "POST":
          form = CommentForm(request.POST)
          if form.is_valid():
              comment = form.save(commit=False)
              comment.post = post
              comment.save()
              return redirect('blog.views.post_detail', pk=post.pk)
      else:
          form = CommentForm()
      return render(request, 'blog/add_comment_to_post.html', {'form': form})
  
  
  def post_new(request):
      if request.method == "POST":
          form = PostForm(request.POST, request.FILES)
          if form.is_valid():
              post = form.save(commit=False)
              post.author = request.user
              post.published_date = timezone.now()
              post.save()
              return redirect('post_detail', pk=post.pk)
      else:
          form = PostForm()
      return render(request, 'blog/add_post.html', {'form': form})
  
  
  def search_view(request):
      if request.method == "POST":
          search_text = request.POST['search-form']
      else:
          search_text = ''
      posts = Post.objects.filter(title__contains=search_text)
      return render_to_response('blog/search.html', {'post': posts})
  
  
  def post_like(request, pk):
      if pk:
          post = Post.objects.get(id=pk)
          count = post.likes
          count += 1
          post.likes = count
          post.save()
      return HttpResponseRedirect('post/%s/like/' % pk)
  
  
  def dislike_post(request, pk):
      if pk:
          post = Post.objects.get(id=pk)
          post.dislikes += 1
          post.save()
      return HttpResponseRedirect('post/%s/like/' % pk)
  </code></pre>
  
  <p>and for urls.py</p>
  
  <pre><code>from django.conf.urls import url
  
  from blog import views
  
  urlpatterns = [
      url(r'^$', views.post_list, name='post_list'),
      url(r'^post/(?P&lt;pk&gt;[0-9]+)/$', views.post_detail, name='post_detail'),
      url(r'^post/(?P&lt;pk&gt;[0-9]+)/comment/$', views.add_comment_to_post, name='add_comment_to_post'),
      url(r'^post/new/$', views.post_new, name='post_new'),
      url(r'^search/$', views.search_view, name='search'),
      url(r'^post/(?P&lt;pk&gt;[0-9]+)/like/$', views.post_like, name='post_like'),
      # url(r'^post/(?P&lt;pk&gt;[0-9]+)/dislike/$', views.dislike_post, name='post_dislike'),
  ]
  </code></pre>
  
  <p>Edit : For the model.py this is the code I use :</p>
  
  <pre><code>class Post(models.Model):
      author = models.ForeignKey('auth.User')
      title = models.CharField(max_length=150)
      text = models.TextField()
      created_date = models.DateTimeField(
          default=timezone.now)
      published_date = models.DateTimeField(
          blank=True, null=True)
      image = VersatileImageField(upload_to='images')
      tags = TaggableManager()
      likes = models.IntegerField(default=0)
      dislikes = models.ImageField(default=0)
      views = models.IntegerField(default=0)
  
      def publish(self):
          self.published_date = timezone.now()
          self.save()
  
      def __str__(self):
          return self.title
  </code></pre>