Much cleanup to better match lesson text

lcthw/ex3.c

@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	int age = 10;
+	int height = 72;
+
+	printf("I am %d years old.\n", age);
+	printf("I am %d inches tall.\n", height);
+
+	return 0;
+}