Let the client tool use decide whether to call schema GET APIs and validate the schemas

> Allow the user to decide, with an additional command option, whether the client tool will call the schema GET APIs and then validate the resposned schema. Once the option is included - the schemas validations (image or member) will be skipped.
> Suggested option name will be - "--noschema"
> This is significant in case of other applications that expose OpenStack APIs: These application may need less focus or won’t expose schema GET APIs at all, and thus the client tool will be able to skip the schema validations.