Include Windows.h instead of windef.h

Unfortunate, because <windef.h> would have been more lightweight, but apparently expects additional
defines to be already set before being included.

Author: Benjamin Kloster

include/cpptrace/utils.hpp

@@ -53,7 +53,7 @@ namespace cpptrace {
 
 
 #if defined(_WIN32)
-    #include <windef.h>
+    #include <Windows.h>
     namespace cpptrace {
         namespace experimental {
             CPPTRACE_EXPORT void load_symbols_for_module(HMODULE hModule);