Changed class of flash messages produced by flask_login to 'info'.

(Redmine issue: #3734)

lib/hawat/app.py

@@ -218,6 +218,7 @@ def _setup_app_auth(app):
     lim = flask_login.LoginManager()
     lim.init_app(app)
     lim.login_view = app.config['HAWAT_LOGIN_VIEW']
+    lim.login_message_category = 'info'
 
     @lim.user_loader
     def load_user(user_id):