Add time functionality

src/main.c

@@ -1,6 +1,7 @@
 #include <stdint.h>
 #include <SDL/SDL.h>
 #include "graphics.c"
+#include "time.c"
 #include "events.c"
 
 unigi_type_error unigi_init() {

src/time.c

@@ -0,0 +1,8 @@
+unigi_type_time_scale unigi_time_clocks_per_sec = 1000;
+unigi_type_time_span unigi_time_get() {
+	return (unigi_type_time_span)SDL_GetTicks();
+}
+
+void unigi_time_sleep(unigi_type_time_span t) {
+	SDL_Delay((unigi_type_time_span)t);
+}