Add system time configuration (#4043)

* Add setting to switch between a fixed start time and the system time

Add clock settings to SDL

Make clock configureable in qt

Add a SharedPage handler class

Init shared_page_handler for tests

src/core/hle/kernel/kernel.cpp

@@ -19,7 +19,6 @@ unsigned int Object::next_object_id;
 /// Initialize the kernel
 void Init(u32 system_mode) {
     ConfigMem::Init();
-    SharedPage::Init();
 
     Kernel::MemoryInit(system_mode);