Add solutions for part 1

tools/builtInChips/DMux.hdl

@@ -0,0 +1,20 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: tools/builtIn/DMux.hdl
+
+/**
+ * Dmultiplexor.  
+ * {a,b} = {in,0} if sel == 0
+ *         {0,in} if sel == 1
+ */
+
+ 
+CHIP DMux {
+
+    IN  in, sel;
+    OUT a, b;
+
+    BUILTIN DMux;
+}
+