Magento 2.0.7 SOAP Wsdl List in Json by default

[davidverholen]

Preconditions

1. Install Magento from 2.0 branch.

Steps to reproduce

1. Install Magento from 2.0 branch.
2. execute curl http://magento_host/soap/default?wsdl_list=1

Expected result

1. Since it is a reference to wsdl resources, I would expect this to be a xml resource by default

Actual result

1. without the "accept: application/xml" Header, a json Object is returned