Escape '.' wildcard in testproj urlregex (#80)

Fix: Django's URL patterns being regexes, '.' has to be escaped to be used as a literal value and not as a joker.

README.rst

@@ -134,7 +134,7 @@ In ``urls.py``:
    )
 
    urlpatterns = [
-      url(r'^swagger(?P<format>.json|.yaml)$', schema_view.without_ui(cache_timeout=None), name='schema-json'),
+      url(r'^swagger(?P<format>\.json|\.yaml)$', schema_view.without_ui(cache_timeout=None), name='schema-json'),
       url(r'^swagger/$', schema_view.with_ui('swagger', cache_timeout=None), name='schema-swagger-ui'),
       url(r'^redoc/$', schema_view.with_ui('redoc', cache_timeout=None), name='schema-redoc'),
       ...