[LIB] improve struct parameters name generated by codegen

[madfelps]

In VM creation, for instance, we use this command:

Inside virtualMachine.CreateParameters, the Image field has two fields (CreateParameterImage0 and CreateParametersImage1) where each of them has only one property (Id and Name, respectively).

It would be better if the Image property have the fields Id and Name directly, instead of CreateParametersImage0 and CreateParametersImage1. The same with others fields as MachineType and Network.

[madfelps]

Also, I believe some return values could have a better name as well. For instance, the List method from virtual_machine returns a ListResult struct, which has ListResultInstances struct parameter, which has ListResultInstancesItem struct parameter (check image below)

Maybe ListResultInstancesItem could be just vm/machine/instance and the others names may follow a more direct and clean name