Update netscript documentation.

Unfortunately, I haven't used most of the specialty APIs yet, so I'm not intimately familiar with where their documentation might be wrong. I figured some fixes were better than no fixes, and I can always make more fixes later.

Fixes #1023.

doc/source/netscript/basicfunctions/prompt.rst

@@ -20,4 +20,4 @@ prompt() Netscript Function
         answer = prompt("Buy a server for $"+cost);
         if(answer) {
             purchaseServer("my server", 8192);
-        }
+        }