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/I2cDevice.cpp

@@ -1,4 +1,5 @@
-#include "I2cDevice.h"
+#include "Tactility/hal/i2c/I2cDevice.h"
+
 #include <cstdint>
 
 bool I2cDevice::readRegister12(uint8_t reg, float& out) const {