[C++] [Qt5]Add support for response compression and various enhancements

Created by: etherealjoy

PR checklist

• Read the contribution guidelines.
• If contributing template-only or documentation-only changes which will change sample output, build the project before.
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cc: @muttleyxd @MartinDelille @stkrwork @ravinikam

Changes

• Support Content-Encoding: gzip, deflate
• Pad response body to error log for negative responses
• add switch to enable content compression, false by default. --additional-properties contentCompression=true
• Linking to zlib will not be done when the contentCompression is inactive

Sample usage

#include <QCoreApplication>
#include <QObject>
#include <QtGlobal>
#include "OAISampleApi.h"

using namespace OpenAPI;
int main(int argc, char *argv[]) {
    Q_UNUSED(argc);
    Q_UNUSED(argv);
    QCoreApplication a(argc, argv);
    auto api = new OAISampleApi();
    api->setHost(QString("172.17.0.2"));
    api->setPort(8080);
    api->enableContentCompression();
    QObject::connect(api, &OAISampleApi::sampleGetV1SignalFull,
               [](OAIHttpRequestWorker *worker, OAIV1_0_response summary){
        Q_UNUSED(summary);
        qDebug() << "response length : " << worker->response.length();
        qDebug() << QString(worker->response) ;
    });
    api->sampleGetV1(0);
    a.exec();
}