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/hal/i2c/I2cMock.cpp

@@ -3,8 +3,8 @@
 /**
  * This code is based on i2c_manager from https://github.com/ropg/i2c_manager/blob/master/i2c_manager/i2c_manager.c (original has MIT license)
  */
-#include "TactilityCore.h"
-#include "I2c.h"
+#include "Tactility/TactilityCore.h"
+#include "Tactility/hal/i2c/I2c.h"
 
 namespace tt::hal::i2c {