title: Django: relation does not exist
body: <p>I have pulled myproject updates from bitbucket and tried following commands  'python3 manage.py makemigrations', 'python3 manage.py migrate vehicle', 'python3 manage.py migrate'. But I am getting the following error. vehicle app is new and some of its models use foreign keys from other apps which were migrated before and are in database. I tried different ways, but cannot find the solution. I am using django-1.7.4 I appreciate any advice. </p>
  
  <pre><code>return _bootstrap._gcd_import(name[level:], package, level)                                                                                            
    File "&lt;frozen importlib._bootstrap&gt;", line 986, in _gcd_import                                                                                           
    File "&lt;frozen importlib._bootstrap&gt;", line 969, in _find_and_load                                                                                        
    File "&lt;frozen importlib._bootstrap&gt;", line 958, in _find_and_load_unlocked                                                                               
    File "&lt;frozen importlib._bootstrap&gt;", line 673, in _load_unlocked                                                                                        
    File "&lt;frozen importlib._bootstrap_external&gt;", line 665, in exec_module                                                                                  
    File "&lt;frozen importlib._bootstrap&gt;", line 222, in _call_with_frames_removed                                                                             
    File "/apps/project/beta/apps/site/admin.py", line 7, in &lt;module&gt;                                                                                         
      from .forms import MenuSubItemAdminForm, MenuChildrenAdminForm                                                                                         
    File "/apps/project/beta/apps/site/forms.py", line 18, in &lt;module&gt;                                                                                        
      class AdvancedVehicleSearchForm(forms.Form):                                                                                                           
    File "/apps/project/beta/apps/site/forms.py", line 24, in AdvancedVehicleSearchForm                                                                       
      make_choices = [(make.id, '{} ({})'.format(make.name, make.stock_count)) for make in Make.objects.get_public().filter(stock_count__gt=0)]              
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/models/query.py", line 141, in __iter__                                       
      self._fetch_all()                                                                                                                                      
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/models/query.py", line 966, in _fetch_all                                     
      self._result_cache = list(self.iterator())                                                                                                             
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/models/query.py", line 265, in iterator                                       
      for row in compiler.results_iter():                                                                                                                    
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/models/sql/compiler.py", line 700, in results_iter                            
      for rows in self.execute_sql(MULTI):                                                                                                                   
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/models/sql/compiler.py", line 786, in execute_sql                             
      cursor.execute(sql, params)                                                                                                                            
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/backends/utils.py", line 81, in execute                                       
      return super(CursorDebugWrapper, self).execute(sql, params)                                                                                            
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/backends/utils.py", line 65, in execute                                       
      return self.cursor.execute(sql, params)                                                                                                                
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/utils.py", line 94, in __exit__                                               
      six.reraise(dj_exc_type, dj_exc_value, traceback)                                                                                                      
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/utils/six.py", line 658, in reraise                                              
      raise value.with_traceback(tb)                                                                                                                         
    File "/apps/project/.virtualenvs/beta/lib/python3.5/site-packages/django/db/backends/utils.py", line 65, in execute                                       
      return self.cursor.execute(sql, params)                                                                                                                
  django.db.utils.ProgrammingError: relation "vehicle_make" does not exist                                                                                   
  LINE 1: ..."."country_id", "vehicle_make"."stock_count" FROM "vehicle_m... 
  </code></pre>
  
  <p>vehicle app, make model:  </p>
  
  <pre><code>from django.db import models
  from django.utils.text import slugify
  from django.core.urlresolvers import reverse
  from django.utils.translation import ugettext_lazy as _
  
  from apps.location.models import Country
  from project.abstract_classes import BaseModel, BaseManager
  from .constants import FUEL_CHOICES, GEARBOX_GROUP_CHOICES, VEHICLE_TYPE_CHOICES
  
  # Create your models here.
  class Make(BaseModel):
      name = models.CharField(_('name'), max_length=50, unique=True, db_index=True)
      country = models.ForeignKey(Country, on_delete=models.CASCADE,
                                      null=True, related_name='makes')
      stock_count = models.PositiveIntegerField(_("Stock count"), default=0)
  
      objects = BaseManager()
  
      class Meta:
          ordering = ['country', 'name']
  
      def __str__(self):
          return self.name      
  
      def get_absolute_url(self):
          return reverse('vehicles-stock-by-make', kwargs={'make': slugify(self.name)})
  </code></pre>
  
  <p>settings.py</p>
  
  <pre><code>INSTALLED_APPS = (
      'django.contrib.admin',
      'easy_thumbnails',
      'adminsortable',
  
      'apps.location',    
      'apps.vehicle',     
  )  
  </code></pre>