precache webgui config files

docs/changelog/6.x.x.txt

@@ -57,6 +57,11 @@
    performance gain while in admin mode.
  - Changed the group and user management interfaces to work and scale better 
    with thousands of users and groups.
+ - Changed the config loader to preload the WebGUI config files into memory at
+   a cost of ~70k (mem) per site for a 2000% performance gain. It is a huge
+   gain, but it was already really fast, so relatively users aren't likely to
+   notice the difference. However, this change helps in the overall
+   scalability of WebGUI under load.
 
 
 6.0.3

docs/gotcha.txt

@@ -29,6 +29,13 @@ save you many hours of grief.
  * Each user's language has been reset to the default language for
 	the site as specified in the profile settings.
 
+ * We removed a bunch of the cryptic-hack code that was allowing
+	backward compatibility all the way back to some 2.x, 3.x, and
+	4.x stuff. To be sure that your site will still work, copy
+	the gateway script (index.pl) over your old one. Also make
+	sure you have extrasPath and extrasURL defined in your config
+	file.
+
 
 6.0.2
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