Fixed build for Qt <5.10, MSVC

src/laybasic/laybasic/layColor.cc

@@ -26,6 +26,7 @@
 #include "tlMath.h"
 
 #include <ctype.h>
+#include <algorithm>
 
 namespace lay
 {

src/laybasic/laybasic/layPixelBuffer.cc

@@ -290,7 +290,7 @@ QImage
 PixelBuffer::to_image_copy () const
 {
   QImage img (m_width, m_height, m_transparent ? QImage::Format_ARGB32 : QImage::Format_RGB32);
-#if QT_VERSION < 0x050000
+#if QT_VERSION < 0x051000
   memcpy (img.bits (), data (), img.byteCount ());
 #else
   memcpy (img.bits (), data (), img.sizeInBytes ());