added game.h player.h and uart.h, implemented game objects

src/game.h

@@ -0,0 +1,26 @@
+#ifndef PLAYER_H
+#define PLAYER_H
+
+#include<stdint.h>
+#include<stdlib.h>
+#include"player.h"
+
+#define PLAYER_COUNT 2
+
+typedef struct game_s{
+    uint16_t time;          // seconds since game start
+    uint8_t winner_id;
+    uint8_t host_id;
+    player_t player[PLAYER_COUNT];
+
+    enum{
+        running,
+        ended
+    } state;
+
+} game_t;
+
+void game_init(game_t* game);
+void game_step(game_t* game, uint16_t time_delta);
+
+#endif /* PLAYER_H */