title: Django admin site not displaying ManyToManyField relationship
body: <p>I'm working on what I think is a pretty standard django site, but am having trouble getting my admin section to display the proper fields.</p>
  
  <p>Here's my models.py:</p>
  
  <pre><code>class Tech(models.Model):
      name = models.CharField(max_length = 30)
  
  class Project(models.Model):
      title = models.CharField(max_length = 50)
      techs = models.ManyToManyField(Tech)
  </code></pre>
  
  <p>In other words, a Project can have different Tech objects and different tech objects can belong to different Projects (Project X was created with Python and Django, Project Y was C# and SQL Server)</p>
  
  <p>However, the admin site doesn't display any UI for the Tech objects. Here's my admin.py:</p>
  
  <pre><code>class TechInline(admin.TabularInline):
      model = Tech
      extra = 5
  
  class ProjectAdmin(admin.ModelAdmin):
      fields = ['title']
      inlines = []
      list_display = ('title')
  
  admin.site.register(Project, ProjectAdmin)
  </code></pre>
  
  <p>I've tried adding the <code>TechInline</code> class to the <code>inlines</code> list, but that causes a </p>
  
  <pre><code>&lt;class 'home.projects.models.Tech'&gt; has no ForeignKey to &lt;class 'home.projects.models.Project'&gt;
  </code></pre>
  
  <p>Error. Also tried adding <code>techs</code> to the <code>fields</code> list, but that gives a </p>
  
  <blockquote>
    <p>no such table: projects_project_techs</p>
  </blockquote>
  
  <p>Error. I verified, and there is no <code>projects_project_techs</code> table, but there is a <code>projects_tech</code> one. Did something perhaps get screwed up in my syncdb? </p>
  
  <p>I am using Sqlite as my database if that helps.</p>