Created by: Kahncode

Fixed the UE4 generator after it had been integrated from my original PR against swagger-codegen. Added the possibility for a codegen to set the location of the generated model files, similarly to API files. Fixed handling of body parameters as per the specification, the single body object is written directly as the payload. Fixed handling of files and binaries, if a field is both isFile and isBinary, file will take precedence.

PR checklist

• Read the contribution guidelines.
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