added basic support for htmx (ajax)

- if there is HX-Request header present we sent only a part of the whole html
- we return only specific stream defined by [out ...] ezc statement
- the name of the stream is passed in the 'frame' parameter
  (if not present then 'content' is assumed)
- added ezc function: winix_is_htmx_request

winixd/templates/winix.cpp

@@ -375,6 +375,15 @@ void winix_locale_tab_name(Info & i)
 }
 
 
+void winix_is_htmx_request(Info & i)
+{
+	if( cur->request->headers_in.has_key(L"HX-Request") || cur->request->headers_in.has_key(L"hx_request") )
+	{
+		// fastcgi will change the header to hx_request
+		i.res = true;
+	}
+}
+