CF9 compatibility fixes

[wellercs]

Several compatibility fixes for ColdFusion 9:

1. index in arguments and local (var) scope threw an error so renamed var index to var ix
2. typeMapping.getJson() was throwing an error without being scoped
3. GetRequest constructor was throwing an error due to missing semi-colon
4. getSourceOnly() was returning undefined and was throwing an error so changed to NOT isNull
5. _url setter inside if getSourceOnly was throwing an error due to missing semi-colon
6. GetResponse exists property default is not being recognized. CF9 sees it as undefined.
7. IResponse was throwing an error saying that the interface cannot have a body
8. http response fixes in Response
9. Response success property default is not being recognized. CF9 sees it as undefined.
10. deserializeJSON(_httpResponse.FileContent fails when _httpResponse.FileContent is java.io.ByteArrayOutputStream