Project restructuring (fixes macOS builds) (#198)

- Create `Include/` folder for all main projects
- Fix some issues here and there (found while moving things)
- All includes are now in `Tactility/` subfolder and must be included with that prefix. This fixes issues with clashing POSIX headers (e.g. `<semaphore.h>` versus Tactility's `Semaphore.h`)

TactilityHeadless/Source/time/Time.cpp

@@ -1,7 +1,10 @@
+#include "Tactility/time/Time.h"
+#include "Tactility/kernel/SystemEvents.h"
+
+#ifdef ESP_PLATFORM
 #include <ctime>
-#include "Time.h"
-#include "Preferences.h"
-#include "kernel/SystemEvents.h"
+#include "Tactility/Preferences.h"
+#endif
 
 namespace tt::time {