CH07: drop ref to "programmable money"

I think this could be confusing.  It's not so much that the money is
programmable---in Bitcoin, your money won't go out and take actions on
its own based on programming.  Instead, Bitcoin allows contracts to be
enforced by deterministic full nodes rather than a more arbitrary justice
system.

chapters/authorization-authentication.adoc

@@ -43,8 +43,7 @@ conditions for spending and how those conditions can be satisfied.
 ((("programmable money")))Bitcoin transaction validation is not based on
 a static pattern, but instead is achieved through the execution of a
 scripting language. This language allows for a nearly infinite variety
-of conditions to be expressed. This is how bitcoin gets the power of
-"programmable money."
+of conditions to be expressed.
 ====
 
 ==== Turing Incompleteness