Readme updated to reflect latest plan for updates

README.md

@@ -9,3 +9,10 @@ The purpose of putting the models here, is to speed up the process of adequately
 easier to make minor tweaks and corrections to the code.  Periodically, we will update the copies available on 
 [patternandprocess.org](http://patternandprocess.org), but the most current versions will be here.
 
+The models as originally released when the book appeared (and as used to generate the figures in the book) are in the folder [`as-released`](/as-released). **These will not change**, and **will not be updated** to remain compatible with later versions of NetLogo. There were written for NetLogo 5.0.x. They will likely work with other NetLogo 5.x versions, but you will need to have the necessary extensions installed. If opened in later versions of NetLogo, the automated translation provided may work, but it might not. This folder is split into a `base-models` folder which should not need any extensions and a `using-R` folder which requires the `r` extension.
+
+Models are being slowly updated, to add more information about how they work and additional in-code comments, and more recently for compatibility with NetLogo 6.x.  The latest versions of the models are in the top level [`base-models`](/base-models) and [`using-R`](/using-R) folders which respectively required no extensions, and one of the NetLogo R extensions (you'll have to download them and try them to find out which).
+
+A 'frozen' final release of these folders compatible with NetLogo 5.3 was created on 18 November, 2017, and is found here.  
+
+The most current code in `base-models` and `using-R` aims to be compatible with the current version of NetLogo.