Fixing existing library after fork

* Updating dependencies to supported versions + changes to get them working
* Updating out of date tests
* Fixes to code/tests for previously submitted update to WSDL version (https://github.com/DDS32/zuora/commit/6ca76ce27c0df9c48ef6e6b6af5322190b0d3019#wsdl/zuora.a.47.1.wsdl)
* All specs (including integrations) now passing