TactilityC additions (#287)

New TactilityC implementations for:
- WiFi
- GPS
- Preferences
- Timezone

Also includes:
- Some fixes to enums/naming
- Cleanup elsewhere

Tactility/Include/Tactility/Preferences.h

@@ -8,9 +8,13 @@ namespace tt {
 /**
  * Settings that persist on NVS flash for ESP32.
  * On simulator, the settings are only in-memory.
+ *
+ * Note that on ESP32, there are limitations:
+ * - namespace name is limited by NVS_NS_NAME_MAX_SIZE (generally 16 characters)
+ * - key is limited by NVS_KEY_NAME_MAX_SIZE (generally 16 characters)
  */
 class Preferences {
-private:
+
     const char* namespace_;
 
 public: