Began work on proper terminal I/O

- Chenged Puts() syscall to Write()
- Improved syscalls.h
- added a new header in terminal/terminal.h
- moved gfxMode into screen/gfxmode.h

include/c/syscall.h

@@ -0,0 +1,23 @@
+#ifndef SYSCALLNUMS_H
+#define SYSCALLNUMS_H
+
+#include <stdint.h>
+
+#define MAX_SYSCALLS 5
+
+typedef enum {
+    SYS_SLEEP, 
+    SYS_WRITE,
+    SYS_GETS,
+    SYS_MALLOC,
+    SYS_FREE,
+} SYSCALL_NUMBERS;
+
+// TODO: Add malloc() and free() syscall wrappers??
+int32_t write(int32_t fd, const void* buf, uint32_t len) {
+    int32_t result = -1;
+    __asm__ volatile ("int $0x80" : "=a"(result) : "a"(SYS_WRITE), "b"(fd), "c"(buf), "d"(len));
+    return result;
+}
+
+#endif