Removed header: "Connection: close"

I'm not sure what my motivation was to put it in there. It has no
place in a CGI program.

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required (VERSION 3.2)
 project(libravatarserv
-        VERSION 0.6.5
+        VERSION 0.6.6
         LANGUAGES CXX
 )
 

src/libravatarserv.cpp

@@ -32,7 +32,6 @@ int main()
 {
     cout << "Server: libravatarserv/" << global::version << endl;
     cout << "Cache-Control: public, max-age=86400\n";
-    cout << "Connection: close\n";
 
     const char *request = std::getenv("REQUEST_URI");
     if (request == nullptr)