Revise Utils::Gzip::decompress

Rename from uncompress to decompress
Change signature
Use proper casting
Use larger buffer for the output of inflate()
Reserve 1 MBytes for output buffer
Change function signature

src/base/net/downloadhandler.cpp

@@ -92,8 +92,8 @@ void DownloadHandler::processFinishedDownload()
             // Success
             QByteArray replyData = m_reply->readAll();
             if (m_reply->rawHeader("Content-Encoding") == "gzip") {
-                // uncompress gzip reply
-                Utils::Gzip::uncompress(replyData, replyData);
+                // decompress gzip reply
+                replyData = Utils::Gzip::decompress(replyData);
             }
 
             if (m_saveToFile) {