Implement UART HAL (#212)

- Implement UART HAL
- Improved I2C and SPI HAL mocking mechanism (removed mock files)

TactilityHeadless/Include/Tactility/hal/uart/UartCompat.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#ifdef ESP_PLATFORM
+
+#include <driver/uart.h>
+#include <driver/gpio.h>
+#include <hal/uart_types.h>
+
+#else
+
+#define UART_NUM_MAX 3
+typedef int uart_port_t;
+
+typedef struct {
+} uart_config_t;
+
+#endif