Add to docs about mapfile requrements
Add to docs about mapfile requrements

The mapfile used must support WMS requests or you'll get back a bunch of ``msWMSDispatch(): WMS server error. WMS request not enabled. Check wms/ows_enable_request settings.`` errors
mapproxy/mapproxy,drnextgis/mapproxy,faegi/mapproxy,faegi/mapproxy,kaiCu/mapproxy,camptocamp/mapproxy,olt/mapproxy,mapproxy/mapproxy,olt/mapproxy,camptocamp/mapproxy,Anderson0026/mapproxy,procrastinatio/mapproxy,vrsource/mapproxy,Anderson0026/mapproxy,vrsource/mapproxy,kaiCu/mapproxy,geoadmin/mapproxy,procrastinatio/mapproxy,drnextgis/mapproxy,geoadmin/mapproxy