Refactor: ModRM Handler replaced with compile-time lookup table.

Started refactoring to a library-based model to easily integrate
comprehensive unit testing. Added CPU exception handling system for
the GUI. Non-critical exceptions (though critical to execution of
emulated application) will not shutdown the application in the future
releases. Refactored Userspace::Run() logic so that the GUI-controls
reflect emulator behavior.

tests/test.cpp

@@ -0,0 +1,21 @@
+#include <gtest/gtest.h>
+
+//#include "../src/Userspace.cpp"
+
+// uint8_t test[] = {
+//   0xB8, 0x10,
+//   0xB9, 0x10,
+//   0x01, 0xC0,
+// };
+
+// Userspace user;
+
+TEST(ModRM_C0, ModRM) {
+  // auto a = user.GetCPUStatus();
+  
+  // user.Upload2Memory(test, 6);
+  // user.Run();
+  
+  //EXPECT_EQ(a.m_Registers[0], 0x20);
+  EXPECT_EQ(1, 1);
+}