Adding keyword args to access WSGI environment doesn't work

[Dennis Plöger]

The method documented here: http://pythonhosted.org/ladon/ladonize.html#access-wsgi-environ-from-service-methods

to access the WSGI environment doesn't work, as "dict" (which is used as the keyword argument) isn't listed in ladon/compat.py in the safe_conversions. Adding a dict: [dict] - line fixes that, though I'm not clear about the implications.