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`)

TactilityCore/Include/Tactility/crypt/Hash.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+
+namespace tt::crypt {
+
+/**
+ * Implementation of DJB2 hashing algorithm.
+ * @param[in] str the string to calculate the hash for
+ * @return the hash
+ */
+uint32_t djb2(const char* str);
+
+/**
+ * Implementation of DJB2 hashing algorithm.
+ * @param[in] data the bytes to calculate the hash for
+ * @param[in] length the size of data
+ * @return the hash
+ */
+uint32_t djb2(const void* data, size_t length);
+
+} // namespace