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/network/Ntp.cpp

@@ -1,8 +1,8 @@
-#include "network/NtpPrivate.h"
+#include "Tactility/network/NtpPrivate.h"
 
 #ifdef ESP_PLATFORM
-#include "kernel/SystemEvents.h"
-#include "TactilityCore.h"
+#include <Tactility/kernel/SystemEvents.h>
+#include <Tactility/TactilityCore.h>
 #include <esp_netif_sntp.h>
 #include <esp_sntp.h>
 #endif