Kernel: Rename MMU to PageTable

This is more descriptive name for what it actually represents

kernel/include/kernel/Memory/PageTableScope.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <kernel/CriticalScope.h>
+#include <kernel/Memory/PageTable.h>
+
+namespace Kernel
+{
+
+	class PageTableScope
+	{
+	public:
+		PageTableScope(PageTable& page_table)
+			: m_old(PageTable::current())
+			, m_temp(page_table)
+		{
+			if (&m_old != &m_temp)
+				m_temp.load();
+		}
+		~PageTableScope()
+		{
+			if (&m_old != &m_temp)
+				m_old.load();
+		}
+	private:
+		CriticalScope m_scope;
+		PageTable& m_old;
+		PageTable& m_temp;
+	};
+
+}