Some things improved

shared_mutex_t implemented
GUI Emu Callbacks rewritten
fxm::import, fxm::import_always implemented
cellMsgDialog rewritten
Emu.CallAfter improved (returns std::future)

Utilities/SharedMutex.h

@@ -0,0 +1,46 @@
+#pragma once
+
+#include <shared_mutex>
+
+// An attempt to create lock-free (in optimistic case) implementation similar to std::shared_mutex;
+// MSVC implementation of std::shared_timed_mutex is not lock-free and thus may be slow, and std::shared_mutex is not available.
+class shared_mutex_t
+{
+	struct ownership_info_t
+	{
+		u32 readers : 31;
+		u32 writers : 1;
+		u16 waiting_readers;
+		u16 waiting_writers;
+	};
+
+	atomic_t<ownership_info_t> m_info{};
+
+	std::mutex m_mutex;
+	
+	std::condition_variable m_rcv;
+	std::condition_variable m_wcv;
+	std::condition_variable m_wrcv;
+	std::condition_variable m_wwcv;
+
+public:
+	shared_mutex_t() = default;
+
+	// Lock in shared mode
+	void lock_shared();
+
+	// Try to lock in shared mode
+	bool try_lock_shared();
+
+	// Unlock in shared mode
+	void unlock_shared();
+
+	// Lock exclusively
+	void lock();
+
+	// Try to lock exclusively
+	bool try_lock();
+
+	// Unlock exclusively
+	void unlock();
+};