[C++ server] Adjust the names (script, sample folder, generator) to lang option (#250)

* Renamce C++ server scripts

* Change output folder

* Rename sample folder: pistache-server -> cpp-pistache

* Rename sample folder: restbed -> cpp-restbed

samples/server/petstore/cpp-pistache/model/ApiResponse.cpp

@@ -0,0 +1,138 @@
+/**
+* OpenAPI Petstore
+* This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+*
+* OpenAPI spec version: 1.0.0
+* 
+*
+* NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+* https://openapi-generator.tech
+* Do not edit the class manually.
+*/
+
+
+#include "ApiResponse.h"
+
+namespace org {
+namespace openapitools {
+namespace server {
+namespace model {
+
+ApiResponse::ApiResponse()
+{
+    m_Code = 0;
+    m_CodeIsSet = false;
+    m_Type = "";
+    m_TypeIsSet = false;
+    m_Message = "";
+    m_MessageIsSet = false;
+    
+}
+
+ApiResponse::~ApiResponse()
+{
+}
+
+void ApiResponse::validate()
+{
+    // TODO: implement validation
+}
+
+nlohmann::json ApiResponse::toJson() const
+{
+    nlohmann::json val = nlohmann::json::object();
+
+    if(m_CodeIsSet)
+    {
+        val["code"] = m_Code;
+    }
+    if(m_TypeIsSet)
+    {
+        val["type"] = ModelBase::toJson(m_Type);
+    }
+    if(m_MessageIsSet)
+    {
+        val["message"] = ModelBase::toJson(m_Message);
+    }
+    
+
+    return val;
+}
+
+void ApiResponse::fromJson(nlohmann::json& val)
+{
+    if(val.find("code") != val.end())
+    {
+        setCode(val.at("code"));
+    }
+    if(val.find("type") != val.end())
+    {
+        setType(val.at("type"));
+        
+    }
+    if(val.find("message") != val.end())
+    {
+        setMessage(val.at("message"));
+        
+    }
+    
+}
+
+
+int32_t ApiResponse::getCode() const
+{
+    return m_Code;
+}
+void ApiResponse::setCode(int32_t value)
+{
+    m_Code = value;
+    m_CodeIsSet = true;
+}
+bool ApiResponse::codeIsSet() const
+{
+    return m_CodeIsSet;
+}
+void ApiResponse::unsetCode()
+{
+    m_CodeIsSet = false;
+}
+std::string ApiResponse::getType() const
+{
+    return m_Type;
+}
+void ApiResponse::setType(std::string value)
+{
+    m_Type = value;
+    m_TypeIsSet = true;
+}
+bool ApiResponse::typeIsSet() const
+{
+    return m_TypeIsSet;
+}
+void ApiResponse::unsetType()
+{
+    m_TypeIsSet = false;
+}
+std::string ApiResponse::getMessage() const
+{
+    return m_Message;
+}
+void ApiResponse::setMessage(std::string value)
+{
+    m_Message = value;
+    m_MessageIsSet = true;
+}
+bool ApiResponse::messageIsSet() const
+{
+    return m_MessageIsSet;
+}
+void ApiResponse::unsetMessage()
+{
+    m_MessageIsSet = false;
+}
+
+}
+}
+}
+}
+