Switch content type depending on SOAP version.

SOAP 1.1 uses a different content type than SOAP 1.2 so we should switch
accordingly. Current version assumes 1.2.
Fix pattern for classes extending SoapClient.

The current pattern has two problems:
- It does not match \SoapClient
- It matches any non-word characters after SoapClient. Thus line breaks and the beginning of docblocks are included and replaced.
Merge branch 'soap11-support'