MULE-7377: WS Consumer ignores imports in WSDL

Changed the RequestBodyGenerator so that if there is a problem when processing the WSDL, an warning is logged but the component doesn't fail (it assumes that the operation requires parameters and therefore will read the SOAP body from the payload).
Merge pull request #429 from mulesoft/MULE-7377

MULE-7377: WS Consumer ignores imports in WSDL