Fix for [TargetNamespace not loaded when import in
schema](https://github.com/vpulim/node-soap/issues/325)
Test-WSDL([Dummy.wsdl](https://github.com/phGitUser/node-soap/blob/master/test/wsdl/Dummy.wsdl))
and
Test-Schemas([Common.xsd](https://github.com/phGitUser/node-soap/blob/master/test/wsdl/Common.xsd),
[Name.xsd](https://github.com/phGitUser/node-soap/blob/master/test/wsdl/Name.xsd))
and writes
[message](https://github.com/phGitUser/node-soap/blob/062f3637198c1fb612aab82788df3aeb0f98dd4c/lib/wsdl.js#L328) to the console when an `targetNamespace` already exists for a
specific Schema and skips the extra Schema