title: drango-allauth Cannot override both Signup and Signin form
body: <p>I'm trying to custom the AllAuth interface.
  I can override LoginForm and SignupForm separately, but if I override both of them, I got this error :</p>
  
  <pre><code>Module "app.forms" does not define a "BootstrapSignupForm" class
  </code></pre>
  
  <p>my forms :</p>
  
  <pre><code>class BootstrapLoginForm(LoginForm):
       def __init__(self, *args, **kwargs):
          super(BootstrapLoginForm, self).__init__(*args, **kwargs)
          self.fields['login'].widget.attrs['class'] = 'form-control';
          self.fields['login'].widget.attrs['placeholder'] = 'User name';
  
          self.fields['password'].widget.attrs['class'] = 'form-control';
          self.fields['password'].widget.attrs['placeholder'] = 'Password';
  
  class BootstrapSignupForm(SignupForm):
       def __init__(self, *args, **kwargs):
          super(BootstrapSignupForm, self).__init__(*args, **kwargs)
          self.fields['username'].widget.attrs['class'] = 'form-control';
          self.fields['username'].widget.attrs['placeholder'] = 'user name';
  </code></pre>
  
  <p>my settings.py</p>
  
  <pre><code>ACCOUNT_FORMS = {'login': 'app.forms.BootstrapLoginForm'}
  ACCOUNT_SIGNUP_FORM_CLASS = 'app.forms.BootstrapSignupForm'
  </code></pre>
  
  <p>But if I only keep one of them, it works.
  Why is it not possible to override many of allauth forms at the same time ? Is there a workaround ? What is the googd practice to change AllAuth theme ? Is there a easy way to set up bootstrap ?</p>