Impacted versions:
Latest Odoo Forum

Steps to reproduce:
Get a nofitication from the Odoo forum (by subscription or by a comment to your posting)

Current behavior:
The notification email contain the subject: "Re: False" and contains no link to the forum post.
Expected behavior:
The notification email contains the title of the forum post and a link to the forum post.
Video/Screenshot link (optional):

![selection_195](https://cloud.githubusercontent.com/assets/1814941/15383579/60b554b0-1d94-11e6-8b1b-875a11e3d82b.png)

addons/website_forum/controllers/main.py
badge_subtype = request.env.ref('gamification.mt_badge_granted')
        if badge_subtype:
            msg = request.env['mail.message'].search([('subtype_id', '=', badge_subtype.id), ('needaction', '=', True)])
        else:
            msg = list()
        return msg
    def _prepare_forum_values(self, forum=None, **kwargs):
        values = {
            'user': request.env.user,
            'is_public_user': request.env.user.id == request.website.user_id.id,
            'notifications': self._get_notifications(),
            'header': kwargs.get('header', dict()),
            'searches': kwargs.get('searches', dict()),
            'forum_welcome_message': request.httprequest.cookies.get('forum_welcome_message', False),
            'validation_email_sent': request.session.get('validation_email_sent', False),
            'validation_email_done': request.session.get('validation_email_done', False),
        }
        if forum:
            values['forum'] = forum
        elif kwargs.get('forum_id'):
            values['forum'] = request.env['forum.forum'].browse(kwargs.pop('forum_id'))
        values.update(kwargs)
        return values
    
    
    @http.route('/forum/send_validation_email', type='json', auth='user', website=True)
    def send_validation_email(self, forum_id=None, **kwargs):