adding first example of character I/O

chapter-01/2-character-io/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -o character-io.x86_64 main.c

chapter-01/2-character-io/main.c

@@ -0,0 +1,11 @@
+#include <stdio.h>
+
+void main()
+{
+    int c;
+
+    while ((c = getchar()) != EOF) {
+        putchar(c);
+        printf("%d", EOF);
+    }
+}