Enable Arduino Uno i2c debugging

src/board/arduino/uno/i2c.c

@@ -0,0 +1,10 @@
+#include <avr/io.h>
+
+#include <board/cpu.h>
+#include <board/i2c.h>
+
+void i2c_init(unsigned long baud) {
+	TWAR = 0;
+	TWBR = (uint8_t)(((F_CPU / baud) - 16 ) / 2);
+	TWCR = 0;
+}