Move interface into a class FrameBase. (PR #893)

. Move the Win32  implementation into Win32Frame.

source/FrameBase.cpp

@@ -0,0 +1,17 @@
+#include "StdAfx.h"
+
+#include "FrameBase.h"
+
+FrameBase::FrameBase()
+{
+	g_hFrameWindow = (HWND)0;
+	g_bConfirmReboot = 1; // saved PageConfig REGSAVE
+	g_bMultiMon = 0; // OFF = load window position & clamp initial frame to screen, ON = use window position as is
+	g_bFreshReset = false;
+	g_hInstance = (HINSTANCE)0;
+}
+
+FrameBase::~FrameBase()
+{
+
+}