Added my own implementation of "Hello world" as an example.

hello.c

@@ -0,0 +1,12 @@
+/*
+ * hello.c
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sysexits.h>
+
+int main(int argc, char** argv) {
+	printf("Hello World.\n");
+	exit(EX_OK);
+}